Sarah invested $500 for 3 years at the investment maturity its value was 578 what was the annual simple interest rate

1) for this exercise you must apply the following formula,

I = C * i*n, where I is the interest, C is the capital initial, i is the rate of interest, and n is time

2) second step

you must * calculate the I = M-C, where M is the final amount and C is the capital

I = 578-500 = 78

3) third step

substitute the values in equation 1

I = C * i * n

78 = 500*i*3⇒i = 78 / (500*3) ⇒i = 0,052 ⇒ 0,05*100 = 5,2% annual interest

The interest rate is 25