Answer:
30 years.
Step-by-step explanation:
The equation for simple interest is I = PRT, where I = interest earned, P = principal/amount invested, R = rate as a decimal, and T = time in years.
Our unknown for this example is T, but first we have to see how much interest is earned.
200 - 80 = 120 in interest (starting with $80, ending with $200)
120 = (80)(0.05)(T)
120 = 4T
30 = T
Please lmk if you have questions.