A persom invests ₹ 12000 as fixed deposit at a bank at the rate of 10% per annum simple interest. But due to some pressing needs, he has to withdraw the entire money after 3 yr for which the bank allowed him a lower rate of interest. If he gets ₹ 3320 less than, what he would have got at the end of 5 yr the rate of interest allowed by bank is
Correct Answer: 77/9%
Explanation:
Let the rate of interest allowed by bank be r%
According to the question,
[(12000 x 5 x 10)/100] - [(12000 x 3 x r)/100] = 3320
⇒ 6000 - 360r = 3320
⇒ 360r = 6000 - 3320 = 2680
⇒ r = 2680/360 = 74/9%
