The DAV Maths Book Class 5 Solutions and DAV Class 5 Maths Chapter 6 Brain Teasers Solutions of Addition and Subtraction of Decimal Numbers offer comprehensive answers to textbook questions.
DAV Class 5 Maths Ch 6 Brain Teasers Solutions
Question 1.
Tick (✓) the correct answers.
(a) How much is 40 more than 12.25?
(i) 27.75
(ii) 28.25
(iii) 27.25
(iv) 28.75
Solution:
We have to subtract to compare the decimal number
So, option (i) is correct.
(b) The digit in the hundredths place in the sum of 3.42, 6.2, and 2.473 is-
(i) 3
(ii) 0
(iii) 2
(iv) 9
Solution:
First, find the sum
So, option (iv) is correct.
(c) 109.93 + _____ = 349.109
(i) 239.179
(ii) 240.179
(iii) 249.279
(iv) 239.279
Solution:
We have to subtract.
So, option (i) is correct
(d) The difference between the greatest and the smallest numbers in the given set of numbers is-
7.018, 7.108, 7.810, 7.081
(i) 0.090
(ii) 0.792
(iii) 0.729
(iv) 0.027
Solution:
Greatest number = 7.810
Smallest number = 7.018
Difference = 0.792
option (ii) is correct.
(e) 0.1 + 0.001 – 0.01 = _____
(i) 0.091
(ii) 0.910
(iii) 0.901
(iv) 0.019
Solution:
option (i) is correct
Question 2.
Find the sum or difference of the following:
(a) 111.1 + 11.11 + 1.111
Solution:
(b) 200.8 – 178.865
Solution:
(c) 43 – 28.625
Solution:
(d) 85 + 8.583 + 85.1
Solution:
Question 3.
The sum of two decimal numbers is 0.9. If one of them is 0.675, find the others.
Solution:
To find the other, we have to subtract it.
The sum of two decimal numbers = 0.900
One of the Numbers = -0.675
Another number = 0.225
Another number is 0.225
Question 4.
A tower is painted in red, white, and black. If 25.5 m is painted red, 15.75 m in black, and 10.25 in white, find the height of the tower.
Solution:
To find the height of the tower, we have to add all the portions.
Length of tower painted red = 25.50
Length of tower painted black = 15.75
Length of tower painted white = +10.25
Height of tower = 51.50
The height of the tower is 51.50 m
Question 5.
The sum of three decimal numbers is 95.3. If two decimal numbers are 43.82 and 26.058 respectively, find the third number.
Solution:
We have to subtract it, the sum of two decimal numbers from the sum of three decimal numbers.
One decimal number = 43.820
Other decimal number = +26.058
The sum of two decimal numbers = 69.878
The sum of three decimal numbers = 95.300
The sum of two decimal numbers = -69.878
Third number = 25.422
The third decimal number is 25.422
Question 6.
Complete the following magic square so that the decimal numbers from left to right and top to bottom add upto to 4.5.
Solution:
IInd row = 1.3 + 1.5 + 1.7 = 4.5
Ist column r1 = 4.5 – (1.3 + 1.4)
= 4.5 – 2.7
= 1.8
For column r2 = 4.5 – (1.1 + 1.5)
= 4.5 – 2.6
= 1.9
For row r3 = 4.5 – (1.8 + 1.1)
= 4.5 – 2.9
= 1.6
For column r4 = 4.5 – (1.6 + 1.7)
= 4.5 – 3.3
= 1.2
Additional Questions
Question 1.
Add.
(a)
Solution:
4.28
(b)
Solution:
3.914
(c)
Solution:
219.86
(d)
Solution:
62.368
Question 2.
Arrange in columns and add.
(a) 3.6 + 5.776 + 0.36
Solution:
(b) 191.3 + 0.236 + 1.133
Solution:
(c) 12.805 + 7.37 + 0.133
Solution:
Question 3.
Subtract.
(a) 7.30 from 9.135
Solution:
(b) 18.355 from 20.13
Solution:
(c) 91.013 from 103.56
Solution:
(d) 33.12 from 90
Solution:
Question 4.
Mr Sahni spent ₹ 50 on shaving, ₹ 90.50 on repairing shoes, and ₹ 120.75 on fruits. Find the total amount he spent.
Solution:
Money spent on shaving = ₹ 50.00
Money spent on repairing shoes = ₹ 90.50
Money spent on fruits = + ₹ 120.75
Amount he spent = ₹ 261.25
The total money he spent is ₹ 261.25.
Question 5.
Fill in the blanks.
(a) 123.50 – _____ = 123.50
Solution:
0
(b) 56.25 – _____ = 0
Solution:
56.25
(c) 430.30 – _____ = 430.30
Solution:
0
(d) 76.361 – _____ = 0
Solution:
76.361
(e) 96.3 – 0 = _____
Solution:
96.3
(f) 79.89 – _____ = 0
Solution:
79.89
Question 6.
Tick (✓) the correct answers.
(a) How much is 80 more than 39.156?
(i) 40.344
(ii) 40.844
(iii) 40.130
(iv) 40.220
Solution:
(ii) 40.844
(b) If we add 0 to 1.339 the answer will be
(i) 1.439
(ii) 1.379
(iii) 1.339
(iv) 1.439
Solution:
(iii) 1.339
(c) 0.624 + 1.234 + 1.8 – 2.555
(i) 1.35
(ii) 1.39
(iii) 0.955
(iv) 1.103
Solution:
(iv) 1.103
Question 7.
Write the digit in the tenths place in the sum of 7.351, 9.253, and 3.56.
Solution:
1
Question 8.
The sum of the two numbers is 107.36. If one of the numbers is 36.7. Find the other number.
Solution:
The sum of two numbers = 107.36
One of the numbers = 36.7
other number = 70.66
Question 9.
Solve
(a) 12.480 + 13.990 – 10
Solution:
16.470
(b) 48.620 + 28.03 – 33.006
Solution:
43.644
(c) 156 + 65.3 – 200.008
Solution:
21.292
(d) 137.12 + 329.1 – 222.463
Solution:
243.757
Question 10.
The length of a wall painted black and white is 156.360 m. 90.76 m is painted black. Find the portion painted white.
Solution:
Length of a wall painted black and white = 156.360 m
Length of a wall painted black = 90.76 m
Length of a wall painted white = 65.6 m
Question 11.
The sum of three decimal numbers is 115.78. If two decimal numbers are 20.368 and 56.12 respectively. Find the third number.
Solution:
The sum of three decimal numbers = 115.78
Sum of two decimal numbers = 20.368 + 56.12 = 76.488
the third number = 39.292