Example 3

A new plumber has just started his own business. In order to try and gain customers, he is running a special for his services. He charges $16 per hour, plus a standard house call fee of $25. Determine the slope of the line that passes through the points of the total cost for jobs lasting from 2 hours to 6 hours. Explain what the slope means in the context of the problem. Finally, use the slope to determine how many hours of work a customer could get for $150. Assume there is no sales tax.
  1. Create a table to show how the two quantities described vary.
  2. Graph the relationship.
  3. Determine the slope and what it means in the context of the problem.
  4. How can the slope be used to determine how many hours of work a customer could get for $150?
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