Final answer:
To calculate the simple annual interest rate, we use the simple interest formula: I = PRT. With the given information, the Hemmings' annual interest rate turns out to be 5%.
Step-by-step explanation:
To find the simple annual interest rate the Hemmings paid, we can use the formula for simple interest: I = PRT, where I is the interest, P is the principal amount, R is the rate of interest per year, and T is the time the money is borrowed for in years.
In the Hemmings' case, they borrowed P = $3,000, paid I = $600 in simple interest, over a period of T = 4 years. We are looking to find R, the simple annual interest rate.
The formula with the known values is:
600 = 3000 × R × 4
To find R, we rearrange the formula:
R = 600 / (3000 × 4)
R = 600 / 12000
R = 0.05
So, R, the simple annual interest rate, is 0.05 or 5%.