NCERT Solutions for Class 7 Maths Chapter 8 – Comparing Quantities. Furthermore, here we’ve provided you with the latest solution for Class 7 Maths Chapter 8 – Comparing Quantities. As a result here you’ll find solutions to all the exercises. This NCERT Class 7 solution will help you to score good marks in your exam.
Students can refer to our solution for NCERT Class 7 Maths Chapter 8 – Comparing Quantities. The Chapter 8 Solution of NCERT will help students prepare for the exams and easily crack the exam. Below we’ve provided you with the exercise-wise latest solution.
NCERT Solutions for Class 7 Maths Chapter 8 – Comparing Quantities Exercise Wise Solution
Exercise 8.1 – Page 157 of NCERT
Exercise 8.2 – Page 164 of NCERT
Exercise 8.3 – Page 171 of NCERT
NCERT Solutions for Class 7 Maths Chapter 8 – Comparing Quantities Exercise 8.1 Solution
Here you’ll find NCERT Chapter 8 – Comparing Quantities Exercise 8.1 Solution.
Exercise 8.1: Solutions of Questions on Page Number: 157
Q1: Find the ratio of:
(a) Rs 5 to 50 paise (b) 15 kg to 210 g
(c) 9 m to 27 cm (d) 30 days to 36 hours
Answer :
- Rs 5 to 50 paise
1 rupee = 100 paise
5 rupee = 500 paise
Hence, the required ratio is 10:1.
- 15 kg to 210 g
1 kg = 1000 g
15 kg = 15000 g
Hence, the required ratio is 500:7.
- 9 m to 27 cm
1 m = 100 cm
9 m = 900 cm
Hence, the required ratio is 100:3.
- 30 days to 36 hours
1 days = 24 hrs
30 days = 24 × 30 = 720 hrs
Hence, the required ratio is 20:1.
Q2: In a computer lab, there are 3 computers for every 6 students. How many computers will be needed for 24 students?
Answer:
For 6 students, number of computers required = 3
For 1 student, number of computers required.
=
For 24 students, number of computers required
=
Hence, 12 computers are required for 24 students.
Q3: Population of Rajasthan = 570 lakhs and population of UP = 1660 lakhs. Area of Rajasthan = 3 lakh km2 and area of UP = 2 lakh km2.
- How many people are there per km2 in both these States?
- Which State is less populated?
Answer:
- Population of Rajasthan in 3 km2 area = 570 lakh
Population of Rajasthan in 1km2 area
=
Population of U.P in 2 km2 area = 1660 lakh
Population of U.P in 1 km2 area
=
= 830 lakh
- It can be observed that population per km2 area is lesser for Rajasthan. Therefore, Rajasthan is less populated.
NCERT Solutions for Class 7 Maths Chapter 8 – Comparing Quantities Exercise 8.2 Solution
Here you’ll find NCERT Chapter 8 – Comparing Quantities Exercise 8.2 Solution.
Exercise 8.2: Solutions of Questions on Page Number: 164
Q1: Convert the given fractional numbers to percents.
(a) 
(c)
Answer:
(a)
(b)
(c)
(d)
Q2: Convert the given decimal fractions to per cents. (a) 0.65 (b) 2.1 (c) 0.02 (d) 12.35
Answer:
(a) 0.65
(b) 2.1
(c) 0.02
(d) 12.35
Q3: Estimate what part of the figures is coloured and hence find the percent which is coloured.
Answer:
- Here, 1 part out of 4 equal parts are shaded which represents the fraction
.
- Here, 3 parts out of 5 equal parts are shaded which represents the fraction
.
- Here, 3 parts out of 8 equal parts are shaded which represents the fraction .
Q4: Find:
(a) 15% of 250 (b) 1% of 1 hour
(c) 20% of Rs 2500 (d) 75% of 1 kg
Answer:
(a)
(b) 1 hour = 60 minutes
(c)
(d)
Q5: Find the whole quantity if
(a) 5% of it is 600 (b) 12% of it is 1080
(c) 40% of it is 500 km (d) 70% of it is 14 minutes
(e) 8% of it is 40 litres
Answer:
(a) 5% of x = 600
(b) 12% of x = Rs 1080
(c) 40% of x = 500 km
(d) 70% of x = 14 min
(e) 8% of x = 40 L
= 500 L
Q6: Convert given percents to decimal fractions and also to fractions in simplest forms:
(a) 25% (b) 150%
(c) 20% (d) 5%
Answer:
(a) 25%
(b) 150%
(c) 20%
(d) 5%
Q7: In a city, 30% are females, 40% are males and remaining are children. What per cent are children?
Answer:
It is given that 30% are females and 40% are males. Children = (100 – 30 – 40) % = 30%
Q8: Out of 15, 000 voters in a constituency, 60% voted. Find the percentage of voters who did not vote. Can you now find how many actually did not vote?
Answer:
Percentage of voters who voted = 60%
Percentage of those who did not vote = 100% – 60% = 40% Number of people who did not vote = 40% of 15000
Therefore, 6000 people did not vote.
Q9: Meeta saves Rs 400 from her salary. If this is 10% of her salary. What is her salary?
Answer:
Let Meeta’s salary be Rs x. Given that,
10% of x = 400
x = 400 × 10 = Rs 4000
Therefore, Meeta’s salary is Rs 4000.
Q10: A local cricket team played 20 matches in one season. It won 25% of them. How many matches did they win?
Answer:
Number of games won = 25% of 20
Therefore, the team won 5 matches.
NCERT Solutions for Class 7 Maths Chapter 8 – Comparing Quantities Exercise 8.3 Solution
Here you’ll find NCERT Chapter 8 – Comparing Quantities Exercise 8.3 Solution.
Exercise 8.3: Solutions of Questions on Page Number: 171
Q1: Tell what is the profit or loss in the following transactions. Also find profit percent or loss percent in each case.
- Gardening shears bought for Rs 250 and sold for Rs 325.
- A refrigerator bought for Rs 12,000 and sold at Rs 13,500.
- A cupboard bought for Rs 2,500 and sold at Rs 3,000.
- A skirt bought for Rs 250 and sold at Rs 150.
Answer:
- Cost price = Rs 250
Selling price = Rs 325
Profit = 325 – 250 = Rs 75
= 
- Cost price = Rs 12000
Selling price = Rs 13,500
Profit = 13500 – 12000 = Rs 1500
Profit % = 
- Cost price = Rs 2500
Selling price = Rs 3000
Profit = 3000 – 2500 = Rs 500
Profit % = 
- Cost price = Rs 250
Selling price = Rs 150
Loss = 250 – 150 = Rs 100
Loss % = 
Q2: Convert each part of the ratio to percentage:
(a) 3:1 (b) 2:3:5 (c) 1:4 (d) 1:2:5
Answer:
(a) 3: 1
Total parts = 3 + 1 = 4
1st part 
2nd part =
(b) 2: 3: 5
Total parts = 2 + 3 + 5 = 10
1st part =
2nd part =
3rd part =
(c) 1: 4
Total parts =1 + 4 = 5
1st part = 
2nd part = 
(d) 1: 2: 5
Total parts = 1 + 2 + 5 = 8
1st part =
2nd part =
3rd =
Q3: The population of a city decreased from 25,000 to 24,500. Find the percentage decrease.
Answer:
Initial population = 25000
Final population = 24500
Decrease = 500
% decrease =
Q4: Arun bought a car for Rs 3,50,000. The next year, the price went upto Rs 3,70,000. What was the percentage of price increase?
Answer:
Initial price = Rs 350000
Final price = Rs 370000
Increase = Rs 20000
% increase =
= 
Q5: I buy a T.V. for Rs 10,000 and sell it at a profit of 20%. How much money do I get for it?
Answer:
Cost price = Rs 10000 Profit = 20% of 10000
= Rs 2000
Selling price = Cost price + Profit
= 10000 + 2000 = Rs 12,000
Q6: Juhi sells a washing machine for Rs 13, 500. She loses 20% in the bargain. What was the price at which she bought it?
Answer:
Selling price = Rs 13500 Loss % = 20%
Let the cost price be x.
Loss = 20% of x
Cost price – Loss = Selling price
= 16875
Therefore, she bought it for Rs 16875.
Q7:
- Chalk contains calcium, carbon and oxygen in the ratio 10:3:12. Find the percentage of carbon in chalk.
- If in a stick of chalk, carbon is 3g, what is the weight of the chalk stick?
Answer:
- Ratio of calcium, carbon, and oxygen = 10:3:12
As 10 + 3 +12 = 25,
Therefore, percentage of carbon
=
- Let the weight of the stick be x g.
12% of x = 3
Q8: Amina buys a book for Rs 275 and sells it at a loss of 15%. How much does she sell it for?
Answer:
Cost price = Rs 275 Loss % = 15% Loss = 15% of 275
Cost price – Loss = Selling price
275 – 41.25 = Selling price Selling price = Rs 233.75
Q9: Find the amount to be paid at the end of 3 years in each case:
- Principal = Rs 1,200 at 12% p.a.
- Principal = Rs 7,500 at 5% p.a.
Answer:
- Principa l (P) = Rs 1200 Rate (R) = 12 % p.a.
Time (T) = 3 years
= Rs 432
Amount = P + S.I.
= 1200 + 432
= Rs 1632
- P = Rs 7500
R = 5% p.a.
T = 3 years
= Rs 1125
Amount = 7500 + 1125
= Rs 8625
Q10: What rate gives Rs 280 as interest on a sum of Rs 56,000 in 2 years?
Answer:
Therefore, 0.25% gives Rs 280 as interest on the given sum.
Q11: If Meena gives an interest of Rs 45 for one year at 9% rate p.a.. What is the sum she has borrowed?
Answer:
= Rs 500
Therefore, she borrowed Rs 500.
NCERT Class 7 Maths All Chapters Solution
Chapter 1: Integers
Chapter 2: Fractions and Decimals
Chapter 3: Data Handling
Chapter 4: Simple Equations
Chapter 5: Lines and Angles
Chapter 6: The Triangle and its Properties.
Chapter 7: Congruence of Triangles
Chapter 8: Comparing Quantities
Chapter 9: Rational Numbers
Chapter 10: Practical Geometry
Chapter 11: Perimeter and Area
Chapter 12: Algebraic Expression
Chapter 13: Exponents and Powers
Chapter 14: Symmetry
Chapter 15: Visualising Solid Shapes