Jasmine invested $73,000 in a fixed rate account offering 7.2% interest rate compounded semiannually. How long will it take her to grow it to $100,000?
let n be the number of half-years
i = .072/2 = .036
73,000(1.036)^n = 100,000
1.036^n = 1.36986...
log both sides and use log rules
n log 1.036 = log 1.36986..
n = 8.898.. half-years
= appr 4.45 years