NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Mathematics (Maths) Class 7

Created by: Praveen Kumar

Class 7 : NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

The document NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev is a part of the Class 7 Course Mathematics (Maths) Class 7.
All you need of Class 7 at this link: Class 7

Exercise 8.3 

Question 1: Tell what is the profit or loss in the following transactions. Also find profit percent or loss percent in each case. 

(a) Gardening shears bought for Rs 250 and sold for Rs 325. 

(b) A refrigerator bought Rs12,000 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 of gardening shears = Rs 250

Selling price of gardening shears = Rs 325
Since, S.P. > C.P., therefore here is profit.
∴ Profit = S.P. - C.P. = Rs 325 - Rs 250 = Rs 75 

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

(b) Cost price of refrigerator = Rs 12,000
Selling price of refrigerator = Rs 13,500
Since, S.P. > C.P., therefore here is profit.
∴ Profit = S.P. - C.P. = Rs 13500 - Rs 12000 = Rs 1,500

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Therefore, Profit = Rs 1,500 and Profit% = 12.5%

(c) Cost price of cupboard = Rs 2,500
Selling price of cupboard = Rs 3,000
Since, S.P. > C.P., therefore here is profit.
∴ Profit = S.P. - CP. = Rs 3,000 - Rs 2,500 = Rs 500

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Therefore, Profit = Rs 500 and Profit% = 20%

(d) Cost price of skirt = Rs 250
Selling price of skirt = Rs 150
Since, C.P. > S.P., therefore here is loss.
∴ Loss = CP, - S.P. = Rs 250 - Rs 150 = Rs100

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Therefore, Profit = Rs 100 and Profit% = 40%


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: (a) 3 :1 

Total part =3 + 1= 4
Therefore, Fractional part = 3/4 : 1/4
⇒ Percentage of parts = NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
⇒ Percentage of parts = 75% : 25%

(b) 2 : 3 : 5

Total part = 2 + 3 + 5 = 10

Therefore, Fractional part =  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

⇒ Percentage of parts  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

⇒ Percentage of parts = 20% : 30% : 50%

(c) 1:4

Total part =1 + 4 = 5

Therefore, Fractional part = 1/5 : 4/5
⇒ Percentage of parts  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
⇒ Percentage of parts = 20%: 00%

(d) 1 : 2 : 5
Total part = 1+ 2 + 5 = 8

Therefore, Fractional part =  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

⇒ Percentage o f parts   NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

⇒ Percentage of parts = 12.5% : 25% : 62.5%


Question 3: The population of a city decreased from 25,000 to 24,500. Find the percentage decrease. 

Answer 3: The decreased population of a city from 25,000 to 24,500.

Population decreased = 25,000 - 24,500 = 500

Decreased Percentage NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Hence, the percentage decreased is 2%.


Question 4: Arun bought a car for Rs 3,50,000. The next year, the price went up to Rs 3,70,000. What was the percentage of price increase? 

Answer 4: Increased in price of a car from Rs 3,50,000 to Rs 3,70,000.

 Amount change = Rs 3,70,000 - Rs 3,50,000 = Rs 20,000.

Therefore, Increased percentage = NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Hence, the percentage of price increased is  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev


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: The cost price of T.V. = Rs 10,000

 profit percent = 20% Now,
 Profit = Profit% of C.P,

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Selling price = C.P. + Profit = Rs 10,000 + Rs 2,000 = Rs 12,000
Hence, he gets Rs 12,000 on selling his T.V.


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: Selling price of washing machine = Rs. 13,500

Loss percent = 20%
Let the cost price of washing machine be Rs x.
Since, Loss = Loss% of C.P.

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
Therefore, S.P. = C.P, - Loss

⇒  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
⇒  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev
⇒  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev


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 3 g, what is the weight of the chalk stick? 

Answer 7: (i) Given ratio = 10 : 3 : 12

Total part = 10 + 3 + 12 = 25 

Part of Carbon = 3/25

Percentage of Carbon part in chalk =  NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

(ii) Quantity of Carbon in chalk stick = 3 g
Let the weight of chalk be x g.
Then, 12 % of x = 3

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Hence, the weight of chalk stick is 25 g.


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: The cost of a book = Rs 275

Loss percent = 15%
Loss = Loss% of C.P. = 1 5 % of Rs 275

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Therefore, S.P. = C.P. - Loss = Rs 275 - Rs 41.25 = Rs 233.75

Hence, Amina sells a book for 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) Here, Principal (P) = Rs 1,200, Rate (R) = 12% p.a., Time (T) = 3 years

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Now, Amount = Principal + Simple Interest
= Rs 1200 + Rs 432 
= Rs 1,632

(b) Here, Principal (P) = Rs 7,500, Rate (R) = 5% p.a., Time (T) = 3 years

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Now, Amount = Principal + Simple Interest
= Rs 7,500 + Rs 1,125
= Rs 8,625


Question 10: What rate gives Rs 280 as interest on a sum of Rs 56,000 in 2 years? 

Answer 10: Here, Principal (P) = Rs 56,000, Simple Interest (S.I.) = Rs 280, Time (T) = 2 years

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Hence, the rate of interest on sum is 0.25%.


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:  Simple Interest = Rs 45, Rate (R) = 9% p.a., Time (T) = 1 years

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

Hence, she borrowed Rs 500.

Complete Syllabus of Class 7

Dynamic Test

Content Category

Related Searches

Exam

,

past year papers

,

Important questions

,

shortcuts and tricks

,

Semester Notes

,

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

,

pdf

,

Summary

,

Extra Questions

,

Free

,

MCQs

,

study material

,

Objective type Questions

,

Viva Questions

,

Previous Year Questions with Solutions

,

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

,

Sample Paper

,

mock tests for examination

,

video lectures

,

ppt

,

practice quizzes

,

NCERT Solutions(Part - 2) - Comparing Quantities Class 7 Notes | EduRev

;