Question

Mike has $500 he wants to save for a big trip in the summer after he graduates from high school. His goal is to find an investment vehicle that will allow his money to double to $1,000 in 4 years. What compound annual interest rate, R, will make this happen?

Answer 1

18.9%

Explanation:

Given data

Principal= $500

Amount=$1000

Time= 4 years

Rate= ???

The compound interest expression is given as

A=P(1+r)^t

when we make "r" the subject of formula we have

r = (A/P)^1/t - 1

substitute

r= (1000/500)^1/4 -1

r= 2^0.25 -1

r= 1.189-1

r= 0.189

Hence the rate is

=0.189*100

=18.9%