# Find Out the Rate Percent? if

In certain time, a sum becomes 4 times at the rate of 5% per annum. At what rate of simple interest the same sum becomes 8 times in the same duration?

- 48/3%
- 58/5%
- 35/3%
- 63/3%

**Answer: (3) 35/3%**

**Explanation:-
**Let the principal be Rs. X

**Given-**

Amount = 4 times of the principal = 4 X, Rate = 5%

**Formula-**

**Simple Interest = P x R x T/100**

**Where, P = principal , R = rate, & T = time.**

Then, 3 X = X x 5 x T/100

3 = T/20

T = 60 years

If principal becomes 8 times in the same duration,

Then, 7 X = X x 60 x R/100

7 = 3 R/5

3 R = 5 x 7

R = 35/3%

Then, the 35/3% rate of simple interest the same sum becomes 8 times in the same duration.

Hence, the answer is (3) 35/3%.