From the question
Kim loaned Barry $15,860 at an interest rate of 16% for 4 years
This implies
Principal (P) = $15,860
Interest Rate (R) = 16%
Time (T) = 4years
We are to find the amount Barry will pay Kim at the end of 4years
First, we need to find the interest I, using

By substituting values we get

Simplifying the expression we have

Hence, the interest to be paid is $10,150.40
Next, we will find the Amount Barry will pay Kim at the end of 4years
Amount (A) is given as

Substituting values

Therefore the Amount to be paid back is $26,010.40