Question

find the interest on rupees 600 at 9% years for 4 years

Answer 1

interest = 600 * 9 * 4 / 100
= 6 *9 *4
= RS 216

Answer 2

Simple Interest =
PRT /100 (principle ✖ rate ✖ time) /100

so. Principle =600
Rate = 9% p.a
Time = 4 years

Interest = 600 ✖ 9 ✖ 4 /100 = 216.