Question

A sum of money if invested at compound interest for $2$ years amounts to Rs. $57,600$ and Rs. $65,536$ in $4$ years. Find the rate and the sum.

Answer 1

Let the sum be $s$

Rate be $r$

For $2$ years ,$57600=s(1+r{)}^2$

For $4$ years ,$65536=s(1+r{)}^4$

$(1+r{)}^2=\frac{65536}{57600}⟹r=0.0667$

$s=50,625$

Answer $r=0.0667,s=50,625$