The simple interest on a sum for 8 years is three-fifth of the sum. The rate of interest per annum is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 7 %.
Let the principal be P and rate of interest be R.
SI = PRT/100
where P is principal, R is rate and T is time.
According to the given question,
(3/5)P = P × R × 8/100
⇒ R = 300/40
⇒ R = 15/2
⇒ R = 7 %