Question

a certain amount becomes 625 times in 4 yrs at compound interest . find the rate of interest

Answer 1

400% will be interest

from 1 ------------> 625..
it took 4 years... So we solve by using
4√625= 5
So Amount at end of 1st year=5
amount at end of 2nd year= 25
amount at end of 3rd year= 125
amount at end of 4th year=625

So Amount at end of 1st year=5
principal= 1
compound interest = 4
So Interest rate = 4/1 *100
=400%