The formula is
A=p (1+r)^t
A future value 4000
P present value 2000
R interest rate?
T time 10 years
4000=2000 (1+r)^10
Solve for r
4000/2000=(1+r)^10
(4000/2000)^(1/10)=1+r
R=(4,000÷2,000)^(1÷10)−1
R=0.07177×100
R=7.177%
The rate is 7.2%.
Compound interest is the interest on a loan or deposit calculated based on the initial principal and the accumulated interest from the previous period.
Given
Sam put 2,000 in a savings account at his bank. After 10 years, his account balance was 4,000.
The rate of interest.
We know the formula
[tex]\rm Amount = Principal (1 + \dfrac{rate}{100})^{time}[/tex]
So we have,
Principal = 2000
Amount = 4000
Time = 10 years
Then according to the formula
[tex]\begin{aligned} 4000 &= \rm 2000 (1 + \dfrac{rate}{100})^{10}\\\\2 &= (1 \rm + \dfrac{rate}{100})^{10}\\\\1.072 &= 1 + \rm \dfrac{rate}{100}\\\\0.072 &= \rm \dfrac{rate}{100}\\\\\rm Rate &= 7.2\\\end{aligned}[/tex]
So the rate is 7.2%.
More about the compound interest link is given below.
https://brainly.com/question/25857212
