The simple interest on a sum for 6 years is three-fifth of the sum. The rate of interest per annum is:
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 10%.
Simple Interest = (P × R × T)/100
Where, P = Principal; R = Rate of interest per annum; T = Total time
Let Principal (P) = 5x
So, total simple interest (I) = 3x
Time (T) = 6 years
Now, 3x = (5x × R × 6)/100 = 3xR/10
⇒ R = 10
Therefore, the rate of interest per annum is 10%.