This is an extension of Lesson 7-7
You can use a graphing calculator to compare two sets of data by using a double box-and-whisker plot. The plots that the calculator draws, however, do not account for outliers. If you want to use a graphing calculator to help you sketch a plot, it will be necessary for you to check for outliers and adjust the graph as needed.
In an experiment, the ability of boys and girls to identify objects held in their left hands versus those held in their right hands was tested. The left side of the body is controlled by the right side of the brain and vice versa. The results of the experiment found that the boys did not identify objects with their right hand as well as with their left. The girls could identify objects equally as welll with either hand.
A graphing calculator company decided to test this premise by conducting the smae tests with 12 male and 10 female employees, chosen ast random. Thirty small objects were selected and separated into two groups - one for the right hand and one for the left hand. Blindfolded employees felt each of the objects with the prescribed hand and tried to identify them. The results are presented in the chart below.
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Make a double box-and-whisker plot of the data to compare the results of Female Left Hand with Female Right Hand using a graphing calculator.
Step 1: Clear lists L1, L2, L3, and L4. Enter the data from each column of the table into lists L1, L2, L3, and L4, respectively.
Step 2: Select the box-and-whisker plot and define which list will be used.
Enter 1 If L1 is not highlighted in the Xlist, use the down arrow and to highlight it and make sure the frequency is set for 1. Repeat the process to assign Plot 2 s a box-and-whisker plot using L2.
Enter 1
If L1 is not highlighted in the Xlist, use the down arrow and to highlight it and make sure the frequency is set for 1.
Repeat the process to assign Plot 2 s a box-and-whisker plot using L2.
Step 3: Clear the Y= likst. Set the WINDOW settings for Xscl = 1, Ymin = 0, and Yscl = 0. Ignore the other settings. Press 9 to select ZoomStat. This sets the other settings and displays the box-and-whisker plots. It will only display those plots that you have turned on.
Step 4: Use to examine the minX (least value), Q1(lower quartile), Med (median), Q3 (upper quartile), and maxX (greatest value).
For Practice: Do 7-7 B Exercises
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