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