## Selina Concise Mathematics Class 7 ICSE Solutions Chapter 1 Integers

**Selina Publishers Concise Mathematics Class 7 ICSE Solutions Chapter 1 Integers**

### Integers Exercise 1A – Selina Concise Mathematics Class 7 ICSE Solutions

Question 1.

Evaluate:

- 427 x 8 + 2 x 427
- 394 x 12 + 394 x (-2)
- 558 x 27 + 3 x 558

Solution:

Question 2.

Evaluate:

- 673 x 9 + 673
- 1925 x 101 – 1925

Solution:

Question 3.

Verify:

- 37 x {8 +(-3)} = 37 x 8 + 37 x – (3)
- (-82) x {(-4) + 19} = (-82) x (-4) + (-82) x 19
- {7 – (-7)} x 7 = 7 x 7 – (-7) x 7
- {(-15) – 8} x -6 = (-15) x (-6) – 8 x (-6)

Solution:

Question 4.

Evaluate:

- 15 x 8
- 15 x (-8)
- (-15) x 8
- (-15) x -8

Solution:

Question 5.

Evaluate:

- 4 x 6 x 8
- 4 x 6 x (-8)
- 4 x (-6) x 8
- (-4) x 6 x 8
- 4 x (-6) x (-8)
- (-4) x (-6) x 8
- (-4) x 6 x (- 8)
- (-4) x (-6) x (-8)

Solution:

Question 6.

Evaluate:

- 2 x 4 x 6 x 8
- 2 x (-4) x 6 x 8
- (-2) x 4 x (-6) x 8
- (-2) x (-4) X 6 x (-8)
- (-2) x (-4) x (-6) x (-8)

Solution:

Question 7.

Determine the integer whose product with ‘-1’ is:

- -47
- 63
- -1
- 0

Solution:

Question 8.

Eighteen integers are multiplied together. What will be the sign of their product, if:

- 15 of them are negative and 3 are positive?
- 12 of them are negative and 6 are positive?
- 9 of them are positive and the remaining are negative?
- all are negative?

Solution:

Question 9.

Find which is greater?

- (8 + 10) x 15 or 8 + 10 x 15
- 12 x (6 – 8) or 12 x 6 – 8
- {(-3) – 4} x (-5) or (-3) – 4 x (-5)

Solution:

Question 10.

State, true or false :

- product of two integers can be zero.
- product of 120 negative integers and 121 positive integers is negative.
- a x (b + c) = a x b + c
- (b – c) x a=b – c x a

Solution:

### Integers Exercise 1B – Selina Concise Mathematics Class 7 ICSE Solutions

Question 1.

Divide:

(i) 117 by 9

(ii) (-117) by 9

(iii) 117 by (-9)

(iv) (-117) by (-9)

(v) 225 by (-15)

(vi) (-552) ÷ 24

(vii) (-798) by (-21)

(viii) (-910) ÷ – 26

Solution :

Question 2.

Evaluate:

(i) (-234) ÷ 13

(ii) 234 ÷ (-13)

(iii) (-234) ÷ (-13)

(iv) 374 ÷ (-17)

(v) (-374) ÷ 17

(vi) (-374) ÷ (-17)

(vii) (-728) ÷ 14

(viii) 272 ÷ (-17)

Solution:

Question 3.

Find the quotient in each of the following divisions:

(i) 299 ÷ 23

(ii) 299 ÷ (-23)

(iii) (-384) ÷ 16

(iv) (-572) ÷ (-22)

(v) 408 ÷ (-17)

Solution:

Question 4.

Divide:

(i) 204 by 17

(ii) 152 by-19

(iii) 0 by 35

(iv) 0 by (-82)

(v) 5490 by 10

(vi) 762800 by 100

Solution:

Question 5.

State, true or false :

- 0 ÷ 32 = 0
- 0 ÷ (-9) = 0
- (-37) ÷ 0 = 0
- 0 ÷ 0 = 0

Solution:

Question 6.

Evaluate:

(i) 42 ÷ 7 + 4

(ii) 12+18 ÷ 3

(iii) 19 – 20 ÷ 4

(iv) 16 – 5 x 3+4

(v) 6 – 8 – (-6) ÷ 2

(vi) 13 -12 ÷ 4 x 2

(vii) 16 + 8 ÷ 4- 2 x 3

(viii) 16 ÷ 8 + 4 – 2 x 3

(ix) 16 – 8 + 4 ÷ 2 x 3

(x) (-4) + (-12) ÷ (-6)

(xi) (-18) + 6 ÷ 3 + 5

(xii) (-20) x (-1) + 14 – 7

Solution:

### Integers Exercise 1C – Selina Concise Mathematics Class 7 ICSE Solutions

Question 1.

Evaluate:

18-(20- 15 ÷ 3)

Solution:

Question 2.

-15+ 24÷ (15-13)

Solution:

Question 3.

35 – [15 + {14-(13 + \(\overline { 2-1+3 }\))}]

Solution:

Question 4.

27- [13 + {4-(8 + 4 – \(\overline { 1+3 }\))}]

Solution:

Question 5.

32 – [43-{51 -(20 – \(\overline { 18 -7 }\))}]

Solution:

Question 6.

46-[26-{14-(15-4÷ 2 x 2)}]

Solution:

Question 7.

45 – [38 – {60 ÷ 3 – (6 – 9 ÷ 3) ÷ 3}]

Solution:

Question 8.

17- [17 — {17 — (17 – \(\overline { 17 -17 }\))}]

Solution:

Question 9.

2550 – [510 – {270 – (90 – \(\overline { 80 + 7 }\))}]

Solution:

Question 10.

30+ [{-2 x (25-\(\overline { 13 -3 }\))}]

Solution:

Question 11.

88-{5-(-48)+ (-16)}

Solution:

Question 12.

9 x (8-\(\overline { 3 +2 }\)) – 2 (2 + \(\overline { 3 +3 }\))

Solution:

Question 13.

2 – [3 – {6 – (5 – \(\overline { 4 -3 }\))}]

Solution:

### Integers Exercise 1D – Selina Concise Mathematics Class 7 ICSE Solutions

Question 1.

The sum of two integers is -15. If one of them is 9, find the other.

Solution:

Question 2.

The difference between an integer and -6 is -5. Find the values of x.

Solution:

Question 3.

The sum of two integers is 28. If one integer is -45, find the other.

Solution:

Question 4.

The sum of two integers is -56. If one integer is -42, find the other.

Solution:

Question 5.

The difference between an integer x and (-9) is 6. Find all possible values ofx.

Solution:

Question 6.

Evaluate:

- (-1) x (-1) x (-1) x ….60 times.
- (-1) x (-1) x (-1) x (-1) x …. 75 times.

Solution:

Question 7.

Evaluate:

- (-2) x (-3) x (-4) x (-5) X (-6)
- (-3) x (-6) x (-9) x (-12)
- (-11) x (-15) + (-11) x (-25)
- 10 x (-12) + 5 x (-12)

Solution:

Question 8.

- If x x (-1) = -36, is x positive or negative?
- If x x (-1) = 36, is x positive or negative?

Solution:

∴ It is a positive integer.

Question 9.

Write all the integers between -15 and 15, which are divisible by 2 and 3.

Solution:

Question 10.

Write all the integers between -5 and 5, which are divisible by 2 or 3.

Solution:

Question 11.

Evaluate:

- (-20) + (-8) ÷ (-2) x 3
- (-5) – (-48) ÷ (-16) + (-2) x 6
- 16 + 8 ÷ 4- 2 x 3
- 16 ÷ 8 x 4 – 2 x 3
- 27 – [5 + {28 – (29 – 7)}]
- 48 – [18 – {16 – (5 – \(\overline { 4 +1 }\))}]
- -8 – {-6 (9 – 11) + 18 = -3}
- (24 ÷ \(\overline { 12 -9 }\) – 12) – (3 x 8 ÷ 4 + 1)

Solution:

Question 12.

Find the result of subtracting the sum of all integers between 20 and 30 from the sum of all integers from 20 to 30.

Solution:

Question 13.

Add the product of (-13) and (-17) to the quotient of (-187) and 11.

Solution:

Question 14.

The product of two integers is-180. If one of them is 12, find the other.

Solution:

Question 15.

- A number changes from -20 to 30. What is the increase or decrease in the number?
- A number changes from 40 to -30. What is the increase or decrease in the number?

Solution: