Example 5

Ernesto built a wooden car for a soap box derby. He is painting the top of the car blue and the sides black. He already has enough black paint, but needs to buy blue paint. He needs to know the approximate area of the top of the car to determine the size of the container of blue paint he should buy. He measured the length to be feet inches, and the width to be inch less than feet. What is the surface area of the top of the car? What is the most accurate area Ernesto can use to buy his paint?
  1. Read the problem statement carefully.
  2. Reread the scenario and make a list of the known quantities.
  3. Read the statement again, identifying the unknown quantity or variable.
  4. Create an equation from the known quantities and variable(s).
  5. Solve the equation for the variable.
  6. Interpret the solution in the context of the problem and convert to the appropriate units if necessary.
  7. Round the result to the appropriate number of places.
This applet is provided by Walch Education as supplemental material for their mathematics programs. Visit www.walch.com for more information on their resources.