Carmen has $90 in a savings account that earns 10% interest per year.The interest is not compounded.How much interest will she earn in 3 years?

Question

Use the formula i = prt, where i is the interest earned, p is the principal (starting amount), r is the interest rate expressed as a decimal, and t is the time in years.

Answer 1

To calculate the interest that Carmen will earn in 3 years using the formula \( i = prt \), we can plug in the values:

• \( p = 90 \) (the principal amount)
• \( r = 0.10 \) (the interest rate as a decimal, which is 10%)
• \( t = 3 \) (the time in years)

Now, substitute these values into the formula:

\[ i = 90 \times 0.10 \times 3 \]

Calculating it step-by-step:

1. Calculate \( 90 \times 0.10 = 9 \)
2. Then, calculate \( 9 \times 3 = 27 \)

So, the interest earned over 3 years is:

\[ i = 27 \]

Carmen will earn $27 in interest in 3 years.