Question

A certain sum amounts to Rs. 5,292 in two years and Rs. 5,556.60 in three years, interest being compounded annually. Find : the rate of interest.

Answer 1

Amount in two years= Rs. 5,292
Amount in three years= Rs. 5,556.60
Difference between the amounts of two successive years
= Rs. 5,556.60 - Rs. 5,292 = Rs. 264.60

⇒ Rs. 264.60 is the interest of one year on Rs. 5,292

∴ Rate of interest = Rs. `[ 100 xx "I"]/[ "P" xx "T"] %`
= `[ 100 xx 264.60 ]/[ 5,292 xx 1 ] %` 
= 5%