Question Kremena took out a \( \$ 500 \) discounted loan for a period of 3 months. The amount she actually received into her bank accoun was \( \$ 460 \). Assuming simple interest rates, what is effective interest rate \( r_{e} \) ? Give your answer as a percentage to the nearest percent.
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To find the effective interest rate \( r_{e} \), we first need to calculate the interest charged on the loan. Kremena borrowed \( \$ 500 \) but only received \( \$ 460 \), meaning the interest for the 3-month period is: \[ \text{Interest} = \text{Loan Amount} - \text{Amount Received} = 500 - 460 = 40 \] The interest rate is then calculated using the formula for simple interest: \[ \text{Interest} = \text{Principal} \times r_{e} \times t \] Where \( t \) is the time in years. Since Kremena took the loan for 3 months, we convert that to years: \[ t = \frac{3}{12} = 0.25 \] Rearranging the formula to solve for \( r_{e} \): \[ r_{e} = \frac{\text{Interest}}{\text{Principal} \times t} = \frac{40}{500 \times 0.25} = \frac{40}{125} = 0.32 \] To express this as a percentage, we multiply by 100: \[ r_{e} = 0.32 \times 100 = 32\% \] Therefore, the effective interest rate \( r_{e} \) is approximately \( 32\% \).