Thread: Impossible Interest question.

At the end of each quarter year, aaron makes a 625 payment into a mutual fund that earns an annual percentage rate of 6%, compounded quarterly. The future value, of aaron's investment is = FV= R[(1+i)^n -1] / i - where n is the number of equal periodic payments of R dollars, and i is the interest rate per compounding period expressed as a decimal. After how long will aaron's investment be worth 1 million?

I did 625 [(1.015^4x)-1] / .015 - wasnt right, tried all variations of 1.06 and 4x, x 1/4x , didnt get it.

Answer s 54.25 years, i got close tho at 54.05 years. But nope, not good enough, if ex. it was a numerical response i would get it wrong still.

Anyone know how to do this, and see what i did wrong?

Hello, skg94!

Your intentions were honorable.
You must have made some elementary errors.

At the end of each quarter-year, Aaron makes a $625 payment into a mutual fund
that earns an annual percentage rate of 6%, compounded quarterly.
The future value, of aaron's investment is: .
. . where = number of equal periodic payments of dollars,
. . and = interest rate per period.
After how long will aaron's investment be worth 1 million dollars?

We have: .

Substitute: .

. . . . . . . . .

Take logs: .

Hence: .


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