When the purpose of solving a problem in measurement is the application of a formula, and not computation, the use of a graphing calculator is not only allowable, but also appropriate.

• Students should begin solving measurement problems by writing down the appropriate formulas on their paper, preserving the necessary grouping symbols.
• Then they should substitute the measurements into the formula(s) that correspond to the variables in the formula(s). They should be reminded to carry over the grouping symbols into the numerical equation(s).
• Instruct students how to transfer their numerical equation from the paper to the calculator. The graphing calculator has a large enough screen that you can see everything that you entered before the calculation is done. They should perform a screen check prior to calculation, making sure that the numbers and symbols have been transposed properly.
• A full discussion about order of operations as well as the use of grouping symbols should be conducted prior to computing with the calculator. Discuss with students whether or not the calculator will do the correct order of operations and how that affects how information is entered into the calculator. Use the formula for surface area of a rectangular prism, SA=2lw+2lh+2wh, as an example. Substitute the values into an overhead calculator and stress the importance of checking your work before pressing enter.
• Now determine the volume of a triangular prism following the steps above: