Answer:
I ≈ 4.0248%
Step-by-step explanation:
The total amount repaid is ...
$2500 +158.15 = $2658.15
so the monthly payment is
$2658.15/(36 mo) = $73.8375/mo
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There is no analytic method by which the interest rate can be calculated, so it must be found by other means, typically by a financial calculator or graphing calculator. The attached shows a graphing calculator result for the interest rate necessary to obtain the above monthly payment, along with a refinement of the result using Newton's Method iteration.
The annual interest rate must be about 4.0248% in order for the total interest on that loan to be $158.15.
The fraction of the workbook he should expect to complete in 1 hour is 5/12
The student's rate is given as:
1/4 of a workbook in 3/5 hour.
The rate in this scenario is calculated using:
Rate = Workbook/time
So, we have:
Rate = 1/4 / 3/5
Express as product
Rate = 1/4 * 5/3
Evaluate
Rate = 5/12
This means that she would complete 5/12 of the workbook in 1 hour
Hence, the fraction of the workbook he should expect to complete in 1 hour is 5/12
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