Question

A bank deposit yields $802.50 in interest every year. How many years will it take to yield 6.42×104
dollars? Write the answer in scientific notation.(1 point)
Responses

8×102
8 times 10 squared

8×104
8 times 10 superscript 4 baseline

8×101
8 times 10 superscript 1 baseline

1.25×102

Answer 1

To determine how many years it will take to yield \( 6.42 \times 10^4 \) dollars in interest at a rate of $802.50 per year, we can use the following formula:

\[
\text{Number of years} = \frac{\text{Total interest}}{\text{Interest per year}}
\]

Plugging in the values:

\[
\text{Number of years} = \frac{6.42 \times 10^4}{802.50}
\]

Calculating the right side:

1. First, calculate \( 6.42 \times 10^4 \):
\[
6.42 \times 10^4 = 64200
\]

2. Now divide by 802.50:
\[
\frac{64200}{802.50} \approx 80
\]

3. Since we need the answer in scientific notation:
\[
80 = 8.0 \times 10^1
\]

Thus, the answer in scientific notation is:

**\( 8 \times 10^1 \)**.

So, the correct response is:

**\( 8 \times 10^1 \)**.