# Find the Rate Percent Per Annum :

The simple interest on a sum of money is 8/25 of the sum. If the number of years is numerically half the rate percent per annum, then the rate percent per annum is

- 5
- 4
- 8
- 25/4

**Answer is (3): 8**

**Explanation:-**Let the principal be Rs. X and rate = R%

Then, the simple interest = 8 X/25 and time = R/2

8 X/25 =X x R X R/100 x 2

8/25 = R^2/2 x 100

8 = R^2 / 2 x 4

R^2 = 8 x 8

square root on both side,

Then, R = 8 %

Hence, the answer is (3) 8.