Question

How long (in years) will it take a $3500 investment in a compound interest account with a 20 percent rate of return to grow to a balance of $112,000?

Answer 1

112000=3500(1+0.20)^t
Solve for t
112000/3500=1.20^t
Log(112000/3500)=t*log(1.20)
t=log(112,000÷3,500)÷log(1.20)
t=19 years