calculating the number of compounding periods

Rounded to the nearest month, how long will it take a town's population to:

b) Shrink from 40,000 to 32,500 if the annual rate of decline is 3?

PV = 40,000

FV = 32,500

n1 = 0.03/1

n = IN ( FV / PV ) / IN ( 1 + i ) In ( 32,500 / 40,000 ) / In ( 1 + 0.3 )

n = - 7.0246 however the answer is 6 years and 10 months

how did they get that ?

calculating the number of compounding periods ( urgent )

$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