## ML Aggarwal Class 7 Solutions for ICSE Maths Chapter 7 Percentage and Its applications Ex 7.4

Question 1.

Find the simple interest on:

(i) ₹ 350 for 2 years at 11% per annum

(ii) ₹ 20000 for 4\(\frac { 1 }{ 2 }\) years at 8\(\frac { 1 }{ 2 }\) % per annum

(iii) ₹ 648 for 8 months at 16\(\frac { 2 }{ 3 }\) % per annum. Also, find the amount in each case.

Solution:

Question 2.

Find the time when:

(i) simple interest on ₹ 2500 at 4% per annum is ₹ 200

(ii) simple interest on ₹ 12000 at 6\(\frac { 1 }{ 2 }\) % per annum is ₹ 2730

Solution:

Question 3.

Find the rate of interest when:

(i) simple interest on ₹ 1560 in 3 years is ₹ 585

(ii) simple interest on ₹ 1625 in 2\(\frac { 1 }{ 2 }\) years is ₹ 325.

Solution:

Question 4.

Find the principal when:

(i) simple interest at 16% per annum for 2\(\frac { 1 }{ 2 }\) years is ₹ 3840

(ii) simple interest at 7\(\frac { 1 }{ 2 }\) % per annum for 2 years 4 months is ₹ 2730.

Solution:

Question 5.

Find the rate of interest when:

(i) ₹ 1200 amounts to ₹ 1320 in 2 years

(ii) ₹ 300 amounts to ₹ 400 in 2 years.

Solution:

Question 6.

Find the time when:

(i) ₹ 1250 amounts to ₹ 1950 at 16% per annum

(ii) ₹ 6540 amounts to ₹ 8447.50 at 12\(\frac { 1 }{ 2 }\) per annum.

Solution:

Question 7.

₹ 14000 is invested at 4% per annum simple interest. How long will it take for the amount to reach ₹ 16240?

Solution:

Question 8.

An amount of money invested trebled in 6 years. Find the rate of interest earned.

Solution:

Question 9.

Find the principal when:

(i) final amount is ₹ 4500 at 20% per annum for 5 years

(ii) final amount is ₹ 2420 at 4% per annum for 2\(\frac { 1 }{ 2 }\) years.

Solution: