SOLUTION: what is the interest rate if I invest $20,000 at the baby's birth in order to have $100,000 in 18 years

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Question 272935: what is the interest rate if I invest $20,000 at the baby's birth in order to have $100,000 in 18 years
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
20,000(1+x)^18=100,000
(1+x)18=100,000/20,000
(1+x)^18=5 take the 18th. root of both sides.
1+x=1.09353
x=1.09353-1
x=.09353 is the required interest rate.