Question

Robert is going to invest $640 and leave it in an account for 20 years. Assuming the interest is compounded quarterly, what interest rate, to the nearest hundredth of a percent, would be required in order for Robert to end up with $1,280?

Answer 1

Answer:

3.48%

Explanation:

1280=640×(1-(r/4))^(4×20)
1280/640=(1-(r/4))^(80)
2=(1-(r/4))^(80)
2=(1-(r/4))^(80)
2^(1/80)=1-(r/4)
1.0087=1-(r/4)
1.0087-1=r/4
0.0087=r/4
R=0.0087×4
R=0.0348
R=0.0348×100
R=3.48%

Answer 2

The answer is: 3.48%

Explanation:

Answer :

R = 3.48%

interset rate