Question

Crystal earns $5.50 per hour mowing lawns.
a. Write a rule to describe how the amount of money m earned is a function of the number of hours h spent mowing lawns.
b. How much does Crystal earn if she works 3 hours and 45 minutes?


m(h) = 5.50h; $20.63





m(h) = 5.50h; $18.98


m(h) = 3h + 45; $61.50

Answer 1

Let's go through the problem step by step:

a. To describe how the amount of money \( m \) earned is a function of the number of hours \( h \) spent mowing lawns, we can write the function as:

\[
m(h) = 5.50h
\]

This means that for every hour \( h \) worked, Crystal earns $5.50.

b. To calculate how much Crystal earns if she works 3 hours and 45 minutes, we first need to convert the time into hours.

3 hours and 45 minutes can be expressed in hours as follows:

\[
3 \text{ hours} + \frac{45 \text{ minutes}}{60} = 3 + 0.75 = 3.75 \text{ hours}
\]

Now we can use the function to find her earnings:

\[
m(3.75) = 5.50 \times 3.75
\]

Calculating that:

\[
m(3.75) = 5.50 \times 3.75 = 20.625
\]

Thus, rounding to two decimal places, Crystal earns approximately:

\[
m(3.75) = 20.63
\]

So, the correct answers are:

a. \( m(h) = 5.50h \)

b. Crystal earns $20.63 if she works 3 hours and 45 minutes.