Math in the Workplace:

A Tale of Two Window Washwers

by Dixie Williford


Meet Tom and Kristy, two window cleaners from Statesboro, Georgia. Though they both live in Statesboro, they are employees of Great Panes Window Cleaning and travel from city to city washing windows for various businesses. We will concentrate on the route that Tom works. Only working two days (three days on occassion) a week, Tom travels from Statesboro to Macon, GA and Walterboro, SC. Tom is given a list of work, and receives 65% of the money collected from each job. He is responsible for driving his own vehicle, purchasing his own work materials (poles, sqeegies, etc..), and for keeping up with his miles travelled (for tax purposes). No taxes are taken out of Tom's pay, so he must budget in order to pay taxes at the end of the fiscal year. All of these conditions create a job that requires a great deal of arithmetic, budgeting and problem-solving. We will look at a few of the situations in which Tom often finds himself.

I. How much does Tom really make in a given month?

Tom claims that he needs to bring home $1000/month in order to pay his bills. As stated previously, Tom only gets to keep 65% of money collected from jobs. His boss recieves the other 35%. Given that Tom works two day a week,collects $400/week, that gas is currently at $1.40/gallon and Tom's Nissan get 31 miles to the gallon (it holds 20 gallons), how much does he really make in a year? Does he make what he needs? After doing your own calculations, click here to check your answer.

II. A "Model" situation.

Luckily for Tom, gas prices have recently been dropping. Below is a table that shows how much he makes a month based on the gas prices for that month (assuming that each gas price remains in place for one).

 Net Income ( in dollars)




 Gas Price (in dollars)





Could a linear function be used to model this data? If not, tell why not.

If so, give the function that best fits the data, plot the data and the "line of best fit." Ask how well your function models the data. What are the implications of your findings for Tom?

What would the gas price have to be for Tom to meet his monthly needs?


Click here to check you solution.

III."Where will Tom lay his head?"

Suppose it is a week in which Tom has two days worth of work in Walterboro. Gas is selling for $1.25/gallon. He knows of a hotel in Walterboro that has rooms for $30/night. Should he stay or go home to Statesboro and return the next day? Which way does he come out on top financially?

Click here to check you answer.