Question

compound interest on rs 20000 @ 10% p.a compounded annually for a certain time is rs 4200.find the time

Answer 1

hey....

amt. = 24200rs
24200= 20000[1+10\100]^t
24200\20000=[11\10]^t
{11\10}^2=[11\10]^t
bases are same equate powers
t=2
so answer is 2years
hope it helps u.....