Instina paid interest charges of 169.05 on a 4830 invoice that was two months overdue What monthly rate of simple interest was she charged? (Do not round Intermediate calculations and round your final answer to 2 decimal places) Monthly rate month

## Step 1: Calculate the total interest for two months.### The problem states that Instina paid an interest of \ 84.525 I = Prt I P r t t = \frac{1}{12} \frac{1}{12} I = \ , 4830 t = \frac{1}{12} r r = \frac{I}{Pt} = \frac{84.525}{4830 \cdot \frac{1}{12}} = \frac{84.525 \cdot 12}{4830} = \frac{1014.3}{4830} \approx 0.21 0.21 \times 100 = 21\%$.