The main objective of providing exercise-wise solutions in PDF is to help students boost their exam preparation. The solutions are designed based on the latest CBSE syllabus and exam pattern. Understanding the concepts before solving the exercise-wise problems is very important to obtain a better score in the exam. The questions present in this exercise have been solved by BYJU’S subject experts in Maths, and these solutions guide students to study well and solve lengthy problems in a shorter duration. The students can download solutions, which are available in PDF format, easily. RD Sharma Solutions for Class 7 Maths Chapter 3 Decimals Exercise 3.1 are provided here. By practising the RD Sharma Solutions for Class 7, students will be able to score high in the annual exam.
RD Sharma Solutions for Class 7 Maths Exercise 3.1 Chapter 3 Decimals
Access answers to Maths RD Sharma Solutions for Class 7 Chapter 3 – Decimals Exercise 3.1
1. Write each of the following as decimals:
(i) (8/100)
(ii) 20 + (9/10) + (4/100)
(iii) 23 + (2/10) + (6/1000)
Solution:
(i) Given (8/100)
Mark the decimal point two places from right to left
(8/100) = 0.08
(ii) Given 20 + (9/10) + (4/100)
First convert the fractions (9/10) and (4/100) to decimals
Consider (9/10)
Mark the decimal point one place from right to left
(9/10) = 0.9
Now consider (4/100)
Mark the decimal point two places from right to left
(4/100) = 0.04
20 + (9/10) + (4/100) = 20 + 0.9 + 0.04
= 20.94
(iii) Given 23 + (2/10) + (6/1000)
First convert the fractions (2/10) and (6/1000) to decimals
Consider (2/10)
Mark the decimal point one place from right to left
(2/10) = 0.2
Now consider (6/1000)
Mark the decimal point three places from right to left
(6/1000) = 0.006
23 + (2/10) + (6/1000) = 23 + 0.2 + 0.006
= 23.206
2. Convert each of the following decimals as fractions:
(i) 0.04
(ii) 2.34
(iii) 0.342
(iv) 17.38
Solution:
(i) Given 0.04
Here we have to convert given decimals into fractions
0.04 can be written as (0.04/1)
Now multiply both numerator and denominator by 100 then we get
(0.04/1) = (0.04 × 100 /1 × 100)
= (4/100)
= (1/25)
(ii) Given 2.34
Here we have to convert given decimals into fractions
2.34 can be written as (2.34/1)
Now multiply both numerator and denominator by 100 then we get
(2.34/1) = (2.34 × 100 /1 × 100)
= (234/100)
= (117/50)
(iii) Given 0.342
Here we have to convert given decimals into fractions
0.342 can be written as (0.342/1)
Now multiply both numerator and denominator by 1000 then we get
(0.342/1) = (0.342 × 1000 /1 × 1000)
= (342/1000)
= (171/500)
(iv) Given 17.38
Here we have to convert given decimals into fractions
17.38 can be written as (17.38/1)
Now multiply both numerator and denominator by 100 then we get
(17.38/1) = (17.38 × 100 /1 × 100)
= (1738/100)
= (869/50)
3. Express the following fractions as decimals:
(i) (23/10)
(ii)
(iii)
(iv)
Solution:
(i) Given (23/10)
Divide 23 by 10 we get
(23/10) = 2.3
(ii) Given
Consider (1/8),
Now multiply both numerator and denominator by 125 to get 1000 as denominator
= 25 + (125/1000)
= 25 + 0.125
= 25.125
(iii) Given
First convert given mixed fraction
By dividing we get
(iv) Given
Consider (1/25),
Now multiply both numerator and denominator by 4 to get 100 as denominator
= 15 + (4/100)
= 15 + 0.04
= 15.04
4. Add the following:
(i) 41.8, 39.24, 5.01 and 62.6
(ii) 18.03, 146.3, .829 and 5.324
Solution:
(i) Given 41.8, 39.24, 5.01 and 62.6
41.8
39.24
5.01
+ 62.6
148.65
(ii) Given 18.03, 146.3, 0.829 and 5.324
18.03
146.3
0.829
+ 5.324
170.483
5. Find the value of:
(i) 9.756 – 6.28
(ii) 48.1 – 0.37
(iii) 108.032 – 86.8
(iv) 100 – 26.32
Solution:
(i) Given 9.756 – 6.28
9.756
– 6.28
3.476
(ii) Given 48.1 – 0.37
48.1
– 0.37
47.73
(iii) Given 108.032 – 86.8
108.032
– 86.8
21.232
(iv) Given 100 – 26.32
100.00
– 26.32
73.68
6. Take out of 3.547 from 7.2
Solution:
Given 3.547 from 7.2
7.2
– 3.547
3.653
7. What is to be added to 36.85 to get 59.41?
Solution:
Given 36.85 and 59.41
Let the unknown number be x
x + 36.85 = 59.41
x = 59.41 – 36.85
x = 22.56
Hence 22.56 is to be added to 36.85 to get 59.41
8. What is to be subtracted from 17.1 to get 2.051?
Solution:
Let the unknown number be x
Given that x is to be subtracted from 17.1 to get 2.051
17.1 – x = 2.051
17.1 – 2.051 = x
x = 17.1 – 2.051
x = 15.049
9. By how much should 34.79 be increased to get 70.15?
Solution:
Let x be the unknown number
x + 34.79 = 70.15
x = 70.15 – 34.79
x = 35.36
35.36 should be increased to 34.79 to get 70.15
10. By how much should 59.71 be decreased to get 34.58?
Solution:
Let x be the unknown number
59.71 – x =34.58
59.71 – 34.58 = x
x = 59.71 – 34.58
x = 25.13
25.13 should be decreased by 59.71 to get 34.58
RD Sharma Solutions for Class 7 Maths Chapter 3 – Decimals Exercise 3.1
RD Sharma Solutions for Class 7 Maths Chapter 3 Decimals Exercise 3.1 have problems based on multiplication and division of decimals. Some of the topics focused on prior to Exercise 3.1 are listed below.
- Definition of decimals
- Types of decimals
- Comparing decimals
- Addition and subtraction of decimals
Comments