Name:________________
Here are the test scores on an exam in Mr. Lund's math class.
Score 100 95 93 79 87 98 89 94 97 81 96
Frequency 2 2 5 1 1 3 2 1 6 1 4
One of the newest ways to display a picture of data, such as test scores, is called a box and whisker plot.
Here is a step-by-step process for making a box and whisker plot. Complete the process by using the data above.
Step 1 Arrange the data from smallest value to largest value.
Step 2 Find the least value and the greatest value.
The lowest test score is_____
The highest test score is____
Step 3 Find the median of the data.
The median is____
Step 4 Find the median of the lower half of the data. (lowest quartile boundary)
The median for the lower half of the test scores is______
Step 5 Find the median of the upper half of the data. (highest quartile boundary)
The median for the upper half of the test score is ______
Step 6 Draw a number line. Below the line, mark the points for the values you found in Steps 2-5.
Step 7 Draw a box from the upper to lower quartile (median) marks. The length of the box is important, but the height (thickness) can be any convenient size.
Step 8 Draw a whisker from the upper quartile mark to the maximum value. Then draw a whisker from the lower quartile mark to the minimum value. At the median of the data set, draw a vertical line within the box from its bottom to its top.
Part 2
Here are the results of a series of chance scores for the dice game Yahtzee.
205 308 246 318 183 254 184 260 248
245 227 189 201 157 263 236 194 148
264 174 194 273 200 173 211 207 225
217 187 203 190 264 254 294 146 195
Use this set of data and your graphing calculator to complete the following exercises.
a. Make a box and whisker plot of the data. Sketch your picture below. Also record the window you use.
b. What are the highest and lowest scores?
c. What is the median score? Is the vertical line in the box "dead center"? Explain.
d. What is the median of the lower half of the data? (lowest quartile)
e. What is the median of the upper half of the data? (upper quartile)
f. Are the whiskers the same length?
g. What does a box and whisker plot not tell you about the data?
Part 3
Use your calculator to draw a box and whisker plot for this set of data. Then answer the questions.
How old would you like to be?
15 18 17 21 18 26 21
22 21 24 19 21 20 27
23 22 28 25 30 21 ~
22 21 20 28 21 16 21
a. What is the median of the data?
b. Which quartile has the largest range?
3. Use your calculator to draw a box and whisker plot for this set of data. Then answer the questions.
How many hours did you spend on homework this past week?
13 4 10 8 9
0 2 5 15 12
9 16 11 8 4
3 8 10 6 8
11 6 7 11 9
a. What is the median number of hours spent on homework?
b. Do you think there is a direct relationship between number of hours spent on homework and grades? Explain.