3.3 Class Limit Calculations

  1. Type in cell C7 the label Lower Limits.
  2. In cell C8, type the formula = C2. This will copy the value in cell C2 as the histogram’s lower limit for the first class.
    1. Select cell C9, and in the formula bar, type =SUM(C8,$C$5). Remember the dollar sign because the value in C5, the width, is a fixed value for all formulas you use here.

Note: You may also do the computation in Step 3 above using the keyboard key +.

  1. Position the mouse pointer in the lower right corner of cell C9 until it becomes a + sign and click, hold, and drag downward until you reach cell C12. Then release.

Note: You should have a total of 5 class limits since your histogram has 5 classes.

Note: If the formulas do not update automatically, do Step 5 below. Otherwise, skip to Step 6.

  1. Select Formulas>Calculate Now.
  2. Type in cell D7 the label Upper Limits.

7.Type the values of the upper limits of each class in cells D8 through D12.

Note: You can also be creative and use a formula to do the work in this step. There are different ways of entering the upper limits using formulas, but that is not being requested from you for this lab.

  1. Type in cell E7 the label Midpoints.
  2. Compute the values of the midpoints (lower limit + upper limit)/2 of each class in cells E8 through E12 by using Excel formulas.

Note: To do this step, use the techniques and Excel functions presented above (create the Excel formula!)

A screenshot of the class limits computations.

Figure 3.2: Class limits computations.