ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress

Question 1.
Match each of the entries in column I with the appropriate entry in column II.
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 1
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 2

Question 2.
(i) From the following table, determines and q if x and y vary directly:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 3
(ii) From the following table, determine a and b if x and y vary inversely:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 4
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 5
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 6

Question 3.
It rained 80 mm in the first 20 days of April. What would be the total rainfall in April?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 7

Question 4.
Mamta earns ₹540 for a working week of 48 hours. If she was absent for 6 hours, how much did she earn?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 8

Question 5.
Navjot can do a piece of work in 6 days working 10 hours per day. In how many days can he do the same work if he increases his working hours by 2 hours per day?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 9

Question 6.
Sharmila has enough money to buy 24 bananas at the rate of ₹ 1·50 per banana. How many bananas she can buy if the price of each orange is decreased by 30 paise?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 10

Question 7.
A fort has rations for 180 soldiers for 40 days. After 10 days, 30 soldiers leave the fort. Find the total number of days for which the food will last.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 11

Question 8.
There are 100 students in a hostel. Food provision for them is for 20 days. How long will these provisions last, if 25 more students join the group?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 12

Question 9.
If 4 goats or 6 sheep can graze a field in 40 days, how many days will 4 goats and 14 sheep take to graze the same field?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 13

Question 10.
A tap can fill a tank in 20 hours, while the other can empty it in 30 hours. The tank is empty and if both taps are opened together, how long will it take for the tank to be half full?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 14

Question 11.
Three ants separately can gobble a grasshopper in 3,4, and 6 days respectively. How many days will they take together to finish off the poor chap? If the grasshopper weighs 63 gram, find the share of each.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 15
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 16

Question 12.
A and B together can do a piece of work in 12 days; B and C together can do it in 15 days. If A is twice as good a workman as C, in how many days A alone will do the same work?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 17
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Check Your Progress 18

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions

Mental Maths
Question 1.
Fill in the blanks:
(i) Two quantities are said to be in direct variation if the increase (or decrease) in one quantity causes in ………….. other quantity.
(ii) Two quantities X and Y are said to be in inverse variation if XY is …………..
(iii) The total cost of articles varies ………….. to the number of articles purchased.
(iv) More work is done in ………….. time.
(v) The time taken to finish work varies ………….. to the number of men at work.
(vi) The speed of a moving object varies inversely to the ………….. to cover a certain distance.
(vii) The number of articles varies ………….. with the cost per article if a fixed amount is available.
(viii)Remuneration is in ………….. of work done.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 1

Question 2.
State whether the following statements are true (T) or false (F):
(i) Two quantities x andy are said to be in inverse variation if \(\frac{x}{y}\) is constant.
(ii) Number of days needed to complete the work = \(\frac{1}{\text { one day’s work }}\)
(iii) Two quantities x andy are said to be in direct variation if x = ky, where k is constant of variation.
(iv) The work done varies inversely to the number of men at work.
(v) In the given time, the distance covered by a moving object varies directly to its speed.
(vi) If A can complete a work in n days, then A’s one day’s work is \(\frac{1}{n}\) of the work, n
(vii) More the money deposited in a bank, more is the interest earned.
(viii) If the number of articles purchased increases the total cost decreases.
(ix) At the same time length of shadow is in direct variation with length of the object.
(x) The distance covered varies inversely to the consumption of petrol.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 2
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 3

Multiple Choice Questions
Choose the correct answer from the given four options (3 to 13):
Question 3.
Two quantities x and y are said to be in inverse variation if
(a) xy = k
(b) x ∝ \(\frac{1}{y}\)
(c) x = \(\frac{k}{y}\)
(d) all of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 4

Question 4.
If 12-metre wire costs ₹24, then the cost of 8-metre wire is
(a) ₹16
(b) ₹20
(c) ₹12
(d) ₹18
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 5

Question 5.
If 5 kg wheat cost ₹60, then cost of 20 kg wheat is
(a) ₹200
(b) ₹210
(c) ₹220
(d) ₹240
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 6

Question 6.
If 10-men can complete a work in 6 days, then 30 men can complete the same work in
(a) 2 days
(b) 3 days
(c) 4 days
(d) 5 days
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 7

Question 7.
A car travels 80 km in 5 litres of petrol, then the distance covered by it in 15 litres of petrol is
(a) 400 km
(b) 240 km
(c) 200 km
(d) 100 km
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 8

Question 8.
In a mess, there was enough food for 200 students for 20 days. If 50 new students joined them, then the food will last for
(a) 15 days
(b) 16 days
(c) 17 days
(d) 18 days
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 9

Question 9.
3 persons can paint a house in 8 days, then 4 persons can paint the same house in
(a) 5 days
(b) 6 days
(c) 7 days
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 10

Question 10.
A photograph of bacteria is enlarged 100000 times attains a length of 5 cm, then actual length of the bacteria is
(a) 0.00005 cm
(b) 5 × 10-5
(c) 5 × 10-7
(d) all of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 11

Question 11.
A tree 12 metre high casts a shadow of length 8 metre. Height of the tree whose shadow is 6 metre in length is
(a) 6 m
(b) 9 m
(c) 15 m
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 12

Question 12.
If 5 pipes can fill the tank in 1 hour, then 4 pipes will fill the tank in
(a) 75 minutes
(b) 70 minutes
(c) 65 minutes
(d) none of these
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 13

Question 13.
A tap fills a tank in 8 hours and another tap at the bottom empties it in 10 hours. If both work together, the tank will be filled in
(a) 18 hours
(b) 24 hours
(c) 36 hours
(d) 40 hours
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 14

Value-Based Questions
Question 1.
The cost of fuel for running a train is proportional to the speed generated in km/h. It costs ₹40 per hour when train is moving with 20 km/h. What would be the cost of fuel per hour, if the train is moving with 60 km/h?
Keeping the safety and fuel prices in mind, state the values promoted in the question.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 15

Question 2.
A pipe can fill a tank in 9 hours. There is a leakage in the bottom of the tank due to which tank is filled in 12 hours. If the tank is full, how much time will leakage take to empty the tank? Should we repair the leakage tank? Should we repair the leakage of the tank immediately? What values are being promoted?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 16

Higher Order Thinking Skills (Hots)
Question 1.
If 8 labourers can earn ₹9000 in 15 days, how many labourers can earn ₹6300 in 7 days?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 17

Question 2.
Three typists working 8 hours a day type a document in 10 days. If only 2 typists are working, how many hours a day should they work to finish the job in 12 days?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Objective Type Questions 18

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3

Question 1.
A farmer can reap a field in 10 days while his wife can do it in 8 days (she does not waste time in smoking). If they work together, in how much time can they reap the field?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 1

Question 2.
A can-do \(\frac{1}{5}\)th of a certain work in 2 days and B can do \(\frac{2}{3}\)rd of it in 8 days. In how much time can they together complete the work?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 2

Question 3.
One tap fills a tank in 20 minutes and another tap fills it in 12 minutes. The tank being empty and if both taps are opened together, in how many minutes the tank will be full?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 3

Question 4.
A can do a work in 6 days and B can do it in 8 days. They worked together for 2 days and then B left the work. How many days will A require to finish the work?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 4
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 5

Question 5.
A can do a piece of work in 40 days. He works at it for 8 days and then B finishes the remaining work in 16 days. How long will they take to complete the work if they do it together?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 6

Question 6.
A and B separately do a work in 10 and 15 Solution: days respectively. They worked together for some days and then A completed the remaining work in 5 days. For how many days had A and B worked together?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 7
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 8

Question 7.
If 3 women or 5 girls take 17 days to complete a piece of work, how long will 7 women and 11 girls working together take to complete the work?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 9

Question 8.
A can do a job in 10 days while B can do it in 15 days. If they work together and earn ₹3500, how should they share the money?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 10

Question 9.
A, B and C can separately do a work in 2, 6 and 3 days respectively. Working together, how much time would they require to do it? If the work earns them ₹1960, how should they divide the money?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 11
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 12

Question 10.
A, B and C together can do a piece of work in 15 days, B alone can do it in 30 days and C alone can do it in 40 days. In how many days will A alone do the work?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 13

Question 11.
A, B and C working together can plough a field in \(4 \frac{4}{5}\) days. A and C together can do it in 8 days. How long would B working alone take to plough the field?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 14

Question 12.
A and B together can build a wall in 10 days; B and C working together can do it in 15 days; C and A together can do it in 12 days. How long will they take to finish the work, working altogether? Also find the number of days taken by each to do the ^ame work, working alone.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 15
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 16

Question 13.
A pipe can fill a tank in 12 hours. By mistake, a waste pipe in the bottom is left opened and the tank is filled in 16 hours. If the tank is full, how much time will the waste pipe take to empty it?
Solution:.
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.3 17

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2

Question 1.
Which of the following are in inverse variation?
(i) The number of students in a hostel and the consumption of food.
(ii) Time is taken by a train to cover a fixed distance and the speed of the train.
(iii) Area of land and its cost.
(iv) The number of people working and the time to complete the work.
(v) The quantity of rice and its cost.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 1

Question 2.
Observe the following tables and find which pair of variables (here x and y) are in inverse variation:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 3

Question 3.
Under the condition that the temperature remains constant, the volume of gas is inversely proportional to its pressure. If the volume of gas is 630 cubic centimetres at a pressure of 360 mm of mercury, then what will be the pressure of the gas, if its volume is 720 cubic centimetres at the same temperature?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 4

Question 4.
A packet of sweets was distributed among 20 children and each of them received 4 sweets. How many sweets will each child get, if the number of children is reduced by 4?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 5

Question 5.
Pooja has enough money to buy 36 oranges at the rate of ₹4.50 per orange. How many oranges she can buy if the price of each orange is increased by 90 paise?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 6

Question 6.
It takes 8 days for 12 men to construct a wall. How many men should be put on the job if it is required to be constructed in 6 days.?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 7

Question 7.
Eight taps through which water flows at the same rate can fill a tank in 27 minutes. If two taps go out of order, how long will the remaining taps take to fill the tank?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 8

Question 8.
A contractor undertook a contract to complete a part of a stadium in 9 months with a team of 560 persons. Later on, it was required to complete the job in 5 months. How many extra persons should he employ to complete the work?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 9

Question 9.
A batch of bottles were packed in 30 boxes with 10 bottles in each box. If the same batch is packed using 12 bottles in each box, how many boxes would be filled?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 10

Question 10.
Vandana takes 24 minutes to reach her school if she goes at a speed of 5 km/h. If she wants to reach school in 20 minutes, what should be her speed?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 11

Question 11.
A fort is provided with food for 80 soldiers to last for 60 days. Find how long would the food last if 20 additional soldiers join after 15 days.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 12

Question 12.
1200 soldiers in a fort had enough food for 28 days. After 4 days, some soldiers were sent to another fort and thus, the food lasted for 32 more days. How many soldiers left the fort?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.2 13

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1

Question 1.
Observe the following tables and find if x and y are directly proportional:
(i)
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1
(ii)
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 2
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 3

Question 2.
If x and y are in direct variation, complete the following tables:
(i)
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 4
(ii)
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 5
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 6
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 7
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 8
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 9

Question 3.
If 8 metres cloth costs ₹250, find the cost of 5·8 metres of the same cloth.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 10
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 11

Question 4.
If a labourer earns ₹672 per week, how much will he earn in 18 days?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 12

Question 5.
If 175 dollars cost ₹7350, how many dollars can be purchased in ₹24024?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 13

Question 6.
If a car travels 67·5 km in 4·5 litres of petrol, how many kilometres will it travel in 26-4 litres of petrol?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 14

Question 7.
If the thickness of a pile of 12 cardboard sheets is 45 mm, then how many sheets of the same cardboard would be 90 cm thick?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 15

Question 8.
In a model of a ship, the mast (flagstaff) is 6 cm high, while the mast of the actual ship is 9 m high. If the length of the ship is 33 m, how long is the model of the ship?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 16

Question 9.
The mass of an aluminium rod varies directly with its length. If a 16 cm long rod has a mass of 192 g, find the length of the rod whose mass is 105 g.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 17

Question 10.
Anita has to drive from village A to village B. She measures a distance of 3.5 cm between these villages on the map. What is the actual distance between the villages if the map scale is 1 cm = 20 km?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 18

Question 11.
A 23 m 75 cm high water tank casts a shadow 20 m long. Find at the same time;
(i) the length of the shadow cast by a tree 9 m 50 cm high.
(ii) the height of the tree if the length of the shadow is 12 m.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 19
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 20

Question 12.
If 5 men or 7 women can earn ₹525 per day, how much would 10 men and 13 women will earn per day.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 9 Direct and Inverse Variation Ex 9.1 21

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress

Question 1.
Find the amount and the compound interest on ₹5000 for 2 years at 6% per annum interest payable yearly.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress 1
Question 2.
Find the amount and the compounded interest on ₹7400 for 1 year at 5% per annum, interest payable half-yearly.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress 2

Question 3.
Find the difference between C.I. and S.l. on a sum of ₹5000 for 2 years at 8% per annum payable yearly.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress 3

Question 4.
Find the amount and compound interest on ₹10000 for \(1 \frac{1}{2}\) years at 10% per annum, compounded half yearly. Would this interest be more than the interest he would get if it was compounded annually?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress 4

Question 5.
What sum invested for \(1 \frac{1}{2}\) years compounded half-yearly at the rate of 4% p.a. will amount to ₹ 132651?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress 5

Question 6.
Find the time (in years) in which ₹ 12500 will produce ₹3246.40 as compound interest at 8% per annum, compounded annually.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress 6

Question 7.
Find the amount and compound interest on ₹2500 in 2 years if the rate are 5% and 6% for the successive years.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Check Your Progress 7

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions

Mental Maths
Question 1.
Fill in the blanks:
(i) The money borrowed (lent or invested) is called …………
(ii) the additional money paid by the borrower to the moneylender in lieu of the money used is called …………
(iii) In simple interest, the principal ………… for the whole loan period.
(iv) In compound interest the ………… goes on changing every conversion period.
(v) The time after which the interest is added each time to form a new principal is called …………
(vi) If the interest is compounded semi-annually then semi-annually rate is ………… of the annual rate.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 1

Question 2.
State whether the following statements are true (T) or false (F):
(i) The interest paid by the banks, post offices, insurance companies is simple interest.
(ii) Compound interest is calculated on the amount of the previous year.
(iii) In compound interest, the principal remains constant for the whole period.
(iv) The time from one specified interest period to the next period is called the conversion period.
(v) If the interest is compounded quarterly then there are 2 conversion periods in a year.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 2

Multiple Choice Questions
Choose the correct answer from the given four options (3 to 9):
Question 3.
The compound interest on ^1000 at 10% p.a. for 2 years is
(a) ₹190
(b) ₹210
(c) ₹1210
(d) ₹200
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 3

Question 4.
The compound interest on ₹5000 at 20% per annum for \(1 \frac{1}{2}\) years compounded half yearly is
(a) ₹6655
(b) ₹1655
(c) ₹50
(d) ₹1000
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 4

Question 5.
The compound interest on ₹10000 at 8% per annum for 6 months compounded quarterly is
a) ₹408
(b) ₹10404
(c) ₹404
(d) ₹400
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 5

Question 6.
The time periods and rate for a sum taken at 8% p.a. for \(1 \frac{1}{2}\) years compounded half yearly are
(a) n = 3, R = 4%
(b) n = 6, R = 2%
(c) n = 3, R = 2%
(d) n = 6, R = 4%
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 6

Question 7.
If ₹12000 taken for 2 years at 4% per annum compounded quarterly, then time period and rate is
(a) n = 2, R = 16%
(b) n = 4, R = 1 %
(c) n = 8, R = 1%
(d) n = 8, R = 16%
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 7

Question 8.
If the number of conversion periods ≥ 2, then compound interest is
(a) less than or equal to the simple interest
(b) greater than or equal to the simple interest
(c) less than simple interest
(d) greater than simple interest
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 8

Question 9.
The time in which ₹6000 amounts to ₹7986 at 10% p.a. compounded annually is
(a) 2 years
(b) 3 years
(c) 4 years
(d) 5 years
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 9

Value Based Question
Question 1.
A person wants to invest ₹ 100000 in fixed deposit scheme for 2 years. His financial advisor explained to him two types of schemes first is yielding 10% p.a. compounded annually, second is yielding 10% p.a. compounded semi-annually. Which scheme is better and why? Why investment is important for future life?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 10

Higher Order Thinking Skills (Hots)
Question 1.
A certain sum of money is invested at the rate of 5% per annum compound interest, the interest compounded annually. If the difference between the interests of the third year and the first year is ₹102.50. Find the sum.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 11
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 12

Question 2.
The difference between the compound interest and the simple interest on ₹42000 for two years is ₹105 at the same rate of interest per annum. Find
(i) the rate of interest
(ii) the compound interest earned in the second year.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 13
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 14
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 15
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Objective Type Questions 16

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3

Question 1.
Calculate the amount and compound interest on
(i) ₹15000 for 2 years at 10% per annum compounded annually.
(ii) ₹156250 for \(1 \frac{1}{2}\) years at 8% per annum compounded half-yearly.
(iii) ₹ 100000 for 9 months at 4% per annum compounded quarterly.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 1
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 2

Question 2.
Find the difference between the simple interest and compound interest on ₹4800 for 2 years at 5% per annum, compound interest being reckoned annually.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 3

Question 3.
Find the compound interest on ₹3125 for 3 years if the rates of interest for the first, second and third year are respectively 4%, 5% and 6% per annum.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 4

Question 4.
Kamla borrowed ₹26400 from a Bank to buy a scooter at a rate of 15% p.a. compounded yearly. What amount will she pay at the end of 2 years and 4 months to clear the loan?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 5

Question 5.
Anil borrowed ₹18000 from Rakesh at 8% per annum simple interest for 2 years. If Anil had borrowed this sum at 8% per annum compound interest, what extra amount would he has to pay?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 6

Question 6.
Mukesh borrowed 775000 from a bank. If the rate of interest is 12% per annum, find the amount he would be paying after \(1 \frac{1}{2}\) years if the interest is
(i) compounded annually
(ii) compounded half-yearly.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 7

Question 7.
Aryaman invested ₹10000 in a company, he would be paid interest at 7% per annum compounded annually. Find
(i) the amount received by him at the end of 2 years.
(ii) the interest for the 3rd year.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 8

Question 8.
What sum of money will amount to ₹9261 in 3 years at 5% per annum compound interest?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 9

Question 9.
What sum invested for \(1 \frac{1}{2}\) years compounded half-yearly at the rate 8% p.a. will amount to ₹ 140608?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 10

Question 10.
At what rate percent will ₹2000 amount to ₹2315·25 in 3 years at compound interest?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 11

Question 11.
If ₹40000 amounts to ₹46305 in \(1 \frac{1}{2}\) years, compound interest payable half-yearly, find the rate of interest per annum.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 12

Question 12.
In what time will ₹15625 amount to ₹ 17576 at 4% per annum compound interest?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 13

Question 13.
₹ 16000 invested at 10% p.a. compounded semi-annually, amounts to ₹18522. Find the time period of investment.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.3 14

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2

Question 1.
Calculate the compound interest on ₹6000 at 10% per annum for two years.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 1

Question 2.
Salma borrowed from Mahila Samiti a sum of ₹ 1875 to purchase a sewing machine. If the rate of interest is 4% per annum, what is the compound interest that she has to pay after 2 years?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 2

Question 3.
Jacob invests ₹12000 for 3 years at 10% per annum. Calculate the amount and the compound interest that Jacob will get after 3 years.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 3

Question 4.
A man invests ₹46875 at 4% per annum compound interest for 3 years.
Calculate:
(i) the interest for the first year.
(ii) the amount standing to his credit at the end of second year.
(iii) the interest for the third year.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 4
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 5

Question 5.
Calculate the compound interest for the second year on ₹6000 invested for 3 years at 10% p.a. Also find the sum due at the end of third year.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 6

Question 6.
Calculate the amount and the compound interest on ₹5000 in 2 years when the rate of interest for successive years is 6% and 8% respectively.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 7

Question 7.
Calculate the difference between the compound interest and the simple interest on ₹20000 in 2 years at 8% per annum.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.2 8

ML Aggarwal Class 8 Solutions for ICSE Maths

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1

ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1

Question 1.
Find the simple interest on ₹4000 at 7.5% p.a. for 3 years 3 months. Also, find the amount.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 1

Question 2.
What sum of money will yield ₹170·10 as simple interest in 2 years 3 months at 6% per annum?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 2

Question 3.
Find the rate of interest when ₹800 fetches ₹130 as a simple interest in 2 years 6 months.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 3

Question 4.
Find the time when simple interest on ₹3·3 lakhs at 6·5% per annum is ₹75075.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 4

Question 5.
Find the sum of money when
(i) simple interest at 7\(\frac{1}{4}\)% p.a. for years is ₹2356·25
(ii) the final amount is ₹ 11300 at 4% p.a. for 3 years 3 months.
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 5
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 6
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 7

Question 6.
How long will it take a certain sum of money to triple itself at 13\(\frac{1}{3}\)% per annum simple interest?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 8

Question 7.
At a certain rate of simple interest ₹4050 amounts to ₹4576·50 in 2 years. At the same rate of simple interest, how much would ₹1 lakh amount to in 3 years?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 9

Question 8.
What sum of money invested at 7.5% p.a. simple interest for 2 years produces twice as much interest as ₹9600 in 3 years 6 months at 10% p.a. simple interest?
Solution:
ML Aggarwal Class 8 Solutions for ICSE Maths Chapter 8 Simple and Compound Interest Ex 8.1 10

ML Aggarwal Class 8 Solutions for ICSE Maths