Q:

Steven invests $20,000 in an account earning 3% interest, compounded annually for 10 years. Three years after Stevens's initial investment, Evan invests $10,000 in an account earning 7% interest, compounded annually for 7 years. Given that no additional deposits are made, compare the amount of interest earned after the interest period ends for each account. (round to the nearest dollar

Accepted Solution

A:
Steven earned $820 more in interest in his account than Evan. What is compound interest?Interest on interest, or compound interest, is the adding of interest to the principal sum of a loan or deposit. It's the outcome of reinvesting interest rather than paying it out so that interest is received on the principal plus previously collected interest in the next quarter. The compound interest earned is given by the formula,[tex]A_1 = P(1+\dfrac{r}{100})^n - P[/tex]In order to compare the two of the given investment, we need to find the interest in each of the investments.For the investment made by Steven of $20,000 at 3% interest compounded annually for 10 years. The interest that Steven made is,[tex]A_1 = P(1+\dfrac{r}{100})^n - P\\\\\\A_1 = 20,00(1+0.03)^{10}-20,000\\\\\\A_1 = \$6,878.33[/tex]For the investment made by Evan of $10,000 at 7% interest compounded annually for 7 years. The interest that Evan made is,[tex]A_2 = P(1+\dfrac{r}{100})^n - P\\\\\\A_2 = 10,00(1+0.07)^{7}-10,000\\\\\\A_2 = \$6,057.82[/tex]Now, if we find the difference in the interest earned by the two of the given person.The difference in the interest earned = Interest earned by Steven - Interest earned by Evan= $6878.33 - $6,057.82= $820.52 ≈ $820Hence, Steven earned $820 more in interest in his account than Evan. Learn more about Compound Interest: