In NCERT Maths Class 7 Chapter 8 Comparing Quantities. We compare the quantities,like kg, g and hours, minute etc.The students learn online and download the solution in pdf from free of cost.
Student can direct access the solution Of:
Exercise 8.1
Exercise 8.2
Exercise 8.3
Download the pdf of Exercise 8.1, Exercise 8.2 and Exercise 8.3.
Class 7 Maths Chapter 8 Solution Exercise 8.1
You can direct access the solution of Class 7 Maths Chapter 8, Exercise 8.2 and Exercise 8.3
Solutions Class 7 Maths Chapter 7
Question 1:
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 1:
(a) Rs. 5 to 50 paise
Rs. 1 = 100 paise
Rs. 5 = 500 paise
⇒ 
(b) 15 kg to 210 g
15 kg = 15×1000 = 15000 g
(c) 9 m to 27 cm
9 m = 9×100 cm =900 cm
(d) 30 days to 36 hours
30 days = 30×24 hours = 720 hours
Question 2:
In a computer lab, there are 3 computers for every 6 students. How many computers will be needed for 24 students?
Answer 2:
Question 3:
Population of Rajasthan = 570 lakhs and population of UP = 1660 lakhs.
Area of Rajasthan = 3 lakh and area of UP = 2 lakh km2 .
(i) How many people are there per km2 in both these States?
(ii) Which State is less populated?
Answer 3:
(ii) It is seen above Rajasthan is less populated.
Maths Chapter 8 Solution Exercise 8.2
Go direct the solution of Class 7 maths Chapter 8 Exercise 8.1 and Exercise 8.3
Question 1:
Convert the given fractional numbers to per cents.
Answer 1:
Question 2:
Convert the given decimal fractions to per cents.
(a) 0.65 (b) 2.1 (c) 0.02 (d) 12.35
Answer 2:
Question 3:
Estimate what part of the figures is coloured and hence find the per cent which is
coloured.
Answer 3:
In Fig. (i), one fourth figure is colored.
Hence percent of one fourth 
In Fig. (ii), three-fifth (3/5) figure is colored.
Hence percent of three – fifth 
In Fig. (iii), three- eighth (3/8) figure is colored.
So, percent of three- eighth 
Question 4:
Find:
(a) 15% of 250 (b) 1% of 1 hour (c) 20% of Rs. 2500 (d) 75% of 1 kg
Answer 4:
Question 5:
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 5:
Question 6:
Convert given per cents to decimal fractions and also to fractions in simplest forms:
(a) 25% (b) 150% (c) 20% (d) 5%
Answer 6:
Question 7:
In a city, 30% are females, 40% are males and remaining are children. What per cent are children?
Answer 7:
We have given Females = 30 % and Males = 40 %
Let total population of the city is 100%
Then percentage of the children = 100% – 30 % – 40% = 30%
Hence the population of children is 30%
Question 8:
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 8:
Voters in constituency = 15000
60 % voted , Therefore not voted people = 40 %
Now not voted people = 40 % of 15000
Therefore, 40 % of 15000
Hence 6000 voters can not voted.
Question 9:
Meeta saves Rs.4000 from her salary. If this is 10% of her salary. What is her salary?
Answer 9:
Hence his salary is Rs. 40000
Question 10:
A local cricket team played 20 matches in one season. It won 25% of them. How many matches did they win?
Answer 10:
Matches played by team = 20
Team won 25% of matches,
Therefore, 25 % of 20 = 
Chapter 8 Exercise 8.3 Solutions
Direct access from here the NCERT Maths solution Class 7 Chapter 8 Exercise 8.1, and Exercise 8.2
Question 1:
Tell what is the profit or loss in the following transactions. Also find profit per cent or loss per cent in each case.
(a) Gardening shears bought for Rs 250 and sold for Rs 325.
(b) A refrigerater bought for Rs 12,000 and sold at Rs 13,500.
(c) A cupboard bought for Rs 2,500 and sold at Rs 3,000.
(d) A skirt bought for Rs 250 and sold at Rs 150.
Answer 1:
(a) Cost price = Rs. 250 and Selling price = Rs. 325
Profit = Sell – Buy
= 325 – 250 = 75
Hence profit is Rs. 75 and profit percent is 30%
(b) Cost price of Refrigerator = Rs. 12000 and selling price = Rs. 13500
Profit = Sell – Buy
= 13500 – 12000 = 1500
Hence profit is Rs. 1500 and profit percent is 12.5%
(c) Cost price of cupboard = Rs. 2500 and selling price = Rs. 3000
Profit = Sell – Buy
= 3000 – 2500 = 500
Hence profit is Rs. 500 and profit percent is 20%
(d) Cost price of shirt = Rs. 250 and selling price = Rs.150
Loss = Buy – sell
= 250 – 150 = 100
Question 2:
Convert each part of the ratio to percentage:
(a) 3 : 1 (b) 2: 3 : 5 (c) 1 : 4 (d) 1 : 2 : 5
Answer 2:
Question 3:
The population of a city decreased from 25,000 to 24,500. Find the percentage decrease.
Answer 3:
Initial population = 25000 and recent population = 24500
Difference in population = 25000 – 24500
= 500
Decreasing percent = 
Question 4:
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 4:
CP of car = Rs. 350000 increased price of car = 370000.
Difference in price = 370000 – 350000 = 20000
Increased percent = 
Question 5:
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 5:
We have given, CP of T.V = 10000 and profit = 20%
So,20 % of 10000 =10000×20/100 =2000
Selling price = C. P + Profit
= 10000 + 2000 = 12000
Hence CP of the T.V is Rs. 12000 .
Question 6:
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 6:
We have given, SP = 13500, Loss = 20%
Let CP is x then
Loss 20% of x =
Question 7:
(i) Chalk contains calcium, carbon and oxygen in the ratio 10:3:12. Find the percentage of carbon in chalk.
(ii) If in a stick of chalk, carbon is 3g, what is the weight of the chalk stick?
Answer 7:
Hence chalk contain calcium, carbon and oxygen in 40%, 12% and 48% respectively.
(ii) We have given carbon is 3g in chalk which is 12 % of the chalk.
Let chalk stick is x g. Therefore 12% of x is 3g, Therefore
Question 8:
Amina buys a book for Rs. 275 and sells it at a loss of 15%. How much does she sell it for?
Answer 8:
We have, CP = Rs.275 and loss = 15%
Now 15% of 275 =
Now, SP = CP – Loss
= 275 – 41.25 = 233.75
Hence Selling price of book is Rs. 233.75
Question 9:
Find the amount to be paid at the end of 3 years in each case:
(a) Principal = Rs. 1,200 at 12% p.a. (b) Principal = Rs. 7,500 at 5% p.a.
Answer 9:
(a) P = 1200 , R = 12 % and T = 3
So, interest of 3 years 
Therefore amount = Principal + interest
= 1200 + 432 = 1632
Hence, amount Rs. 1632 is paid after 3 years.
(b) P = 7500 , R = 5 % and T = 3
So, interest of 3 years =
Therefore amount = Principal + interest
= 7500 + 1125 = 8625
Hence, Rs. 8625 is paid after 3 years.
Question 10:
What rate gives Rs. 280 as interest on a sum of Rs. 56,000 in 2 years?
Answer 10:
We have given, I = 280 , P = 56000 , T = 2, R = ?
Question 11:
If Meena gives an interest of Rs. 45 for one year at 9% rate p.a.. What is the sum she has borrowed?
Answer 11:
We have given , I = Rs. 45, R = 9% T = 1 year and P =?
