Answer: 448 dollars
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Work Shown:
P = 400 is the balance
r = 0.12 is the decimal form of the interest rate
t = 1 is the number of years
Use those values to get the simple interest to be
i = P*r*t
i = 400*0.12*1
i = 48
The amount of interest charged is $48
Add this onto the balance of 400 dollars and the total amount Aaron owes is P+i = 400+48 = 448 dollars.
