Jacob invested $300 in a savings account and earned $81 in simple interest at the end of 9 years. what was the interest rate a) 3% b) 3.5% c) 4% d) 4.5%

A.

Step-by-step explanation:

We use the simple interest equation of A=P(1+rt).

A-the total amount with interest earned

P-the initial amount or principal

r-rate

t-time in years

We substitute the values P=300, A=381, and t=9. We then solve for r.

We divide both sides by 300.

Simplify.

We subtract 1 from both sides.

Simplify.

We divide by 9.

r=0.03

We need to convert the decimal to a percentage by multiplying by 100.

The interest rate is 3%.