SSC CGL 2022151)A person deposited ₹15,600 in a fixed deposit at 10% per annum simple interest. After every second year he adds his interest earned to the principal. The interest at the end of 4 years is:
₹6,864
SSC CGL 2022152)A sum of money doubles itself in 7 years at simple interest. In how much time will it become 5 times of itself?
28 years