₹9000 becomes ₹18000 at simple interest in 8 years. Find the rate per cent per annum.

Solution:

Given, ₹9000 becomes ₹18000 at simple interest in 8 years.

We have to find the rate percent per annum

According to the question,

P = ₹9000

A = ₹18000

We know, A = P + I

18000 = 9000 + I

I = 18000 - 9000

I = ₹9000

We know, I = P×R×T/100

9000 = 9000 × R × 8 /100

100 = R × 8

R = 100/8

R = 12.5%

Therefore, the rate of interest is 12.5%

✦ Try This: A certain sum of money lent out at simple interest amounts to Rs. 1,550 in three years and Rs.1,750 in five years. Find the principal and the rate of interest.

☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 8

NCERT Exemplar Class 7 Maths Chapter 7 Problem 132

₹9000 becomes ₹18000 at simple interest in 8 years. Find the rate per cent per annum.

Summary:

₹9000 becomes ₹18000 at simple interest in 8 years. The rate of interest is 12.5% per annum.

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