Question

1. after 4 years, $9,000 deposited in a savings account with simple interest had earned $1,440 in interest. what was the interest rate?
2. 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.

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Explanation:

Step1: List given values

$I = 1440$, $p = 9000$, $t = 4$

Step2: Rearrange formula for $r$

$r = \frac{I}{pt}$

Step3: Substitute values into formula

$r = \frac{1440}{9000 \times 4} = \frac{1440}{36000}$

Step4: Calculate decimal rate

$r = 0.04$

Step5: Convert to percentage

$0.04 \times 100 = 4$

Answer:

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