question_answer

Arun invested a sum of money at a certain rate of S.I. for a period of 4 year. Had he invested the same sum for a period of 6 years, the total interest earned by him would have 50% more than earlier interest amount, what was the rate of interest per annum?

A) 4%

B) 8%

C) 5%

D) can't be determined

E) None of these