Algebra question (Exponential Growth)

Question

John has a job that pays $7.50 per hour and will get a 2% raise every 3 months. What will his rate of pay be in 2 years?

Answer 1

After the first 3 month his salary will be 7.50* .02 + 7.50 = 7.50(.02 + 1) = 1.02 * 7.50

After             6 months                 1.02 * 7.50 * 0.02 + 1.02 * 7.50 = 1.02(7.50 * .02 + 7.50 * 1) = 1.02* 7.50 * 1.02

                                                or 1.02 exp 2 * 7.50

After             9 month                   7.50 * 1.02 exp 3

                   12 month                  7.50 * 1.02 exp 4

After two years:                           7.50 * 1.02 exp 8

Solving the equation using a calculator :    7.50 * 1.17 = 8.79

In two years the job will pay $8.79 per hour.