calculating the number of compounding periods

$7500 was borrowed for a 4 year term at 9% compounded quarterly.The terms of the loan allow prepayment of the loan based on discounting the loan's maturity value at 7% compounded quarterly How long ( to the nearest day ) before the maturity date was the loan prepaid if the payout amount was $9380.24 including accrued interest ? for the puropese of determining the number of days in a partial calendar quarter, assume that a full quarter has 91 days.

FV = 9380.24

PV = 7500

n =

i = ( confused on )

n = ?

because of the 7% ccompounded quarterly and 9 % compounded quarterly both of them threw me off so i am stuck