Question

How much will you need to invest at 3% to have earned $900 in interest in 4 years?

Answer 1

You will have earned $113 in interest.

Explanation:

After investing for 4 years at 3% interest, your initial investment of $900 will have grown to $1,013.

Answer 2

To find the amount you need to invest, we can use the formula for simple interest:

`\displaystyle\sf \text{{Interest}} = \text{{Principal}} * \text{{Rate}} * \text{{Time}}`

Here, the principal is the amount you need to invest, the rate is 3% (or 0.03 as a decimal), and the time is 4 years. We can rearrange the formula to solve for the principal:

`\displaystyle\sf \text{{Principal}} = \frac{{\text{{Interest}}}}{{\text{{Rate}} * \text{{Time}}}}`

Plugging in the given values, we get:

`\displaystyle\sf \text{{Principal}} = \frac{{900}}{{0.03 * 4}}`

Simplifying further:

`\displaystyle\sf \text{{Principal}} = \frac{{900}}{{0.12}}`

Calculating the division:

`\displaystyle\sf \text{{Principal}} = 7500`

Therefore, you will need to invest $7500 at 3% to have earned $900 in interest in 4 years.