A grocery store employee earns $15 an hour. He earns $20 an hour for each hour over 40 that he works in the week. Use the graph to solve for how much he will make for the week if he works 55 hours.

To solve for how much the grocery store employee will make for the week if he works 55 hours, we need to calculate the total earnings.

First, we calculate the base salary for the first 40 hours:
$15/hour * 40 hours = $<<15*40=600>>600

Next, we calculate the additional earnings for the extra 15 hours:
$20/hour * 15 hours = $<<20*15=300>>300

Finally, we add the base salary and extra earnings together to find the total earnings for the week:
$600 + $300 = $<<600+300=900>>900

Therefore, if the grocery store employee works 55 hours in a week, he will make $900.