Problema Solution

Nicole used her credit card to buy a $1,255 mattress. Her credit card has an APR of 11.56%, compounded monthly, and the mattress was the only purchase on the card. Nicole paid off the mattress after two and a half years. If the sales tax in Nicole’s area is 9.08%, how much interest did Nicole pay in total? (Round all dollar values to the nearest cent.)

Answer provided by our tutors

the sales tax is 9.08% of $1,255:


1255 *.0908= $113.954


the cost of the mattress is:


1255+113.954= $1368.954


now we can consider:


P = $1368.954 principal


r = 0.1156 or 11.56%


t = 2.5 years


n = 12*2.5 = 30


A = the future value


A = 1368.954(1+0.1156/12)^(2.5*12)


A = $1825.15


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the interest paid is the difference:


1825.15 - 1368.954 = $456.20


$456.20 interest paid by Nicole.