Diego decided to invest his $500 tax refund rather than spending it. He found a bank that would pay him 4% interest, compounded quarterly. I

I am assuming that you mean 4% per annum, that is 1% or 0.01 per quarter

FV=PV(1+i)ⁿ

1000=500(1+0.01)ⁿ

2=1.01ⁿ

log2 = log1.01ⁿ

log2 = nlog1.01

n=log2 / log1.01

n=69.66 quarters

time = 70/4 = 17.5 years

Thanks for that answer, Melody.....Note something interesting.....The time it takes to double his money under these conditions is independent of what he started with...In other words, it would take him as long to double $1M as it would $500......... ( )