1. Box and Whisker Plots

2. mean Add everything up and divide by the number of data points.
Ex. Find the mean of the data set: 3, 4, 6, 8, 3

3. median Middle point of the data To calculate:
Put the values in order from smallest to largest
If there is an odd number of data points, value in the middle
If there is an even number of data points, average the two middle values
Ex. Find the median of the data set: 6, 3, 9, 1, 7, 8, 3, 5, 3, 2, 7, 3, 8, 4, 9, 10

4. mode Value that occurs most frequently
If no value occurs more than once, then the data set has no mode
Data set can have more than one mode
Ex. Find the mode of the data set:
7, 4, 9, 2, 4, 3, 9, 1, 7, 8, 3, 2, 3, 3, 3, 5, 2

5. Example 1 Data Set I Data Set II Mean is ____ Median is ____
Mode is ____
Data Set II
Data Set II

6. Solution Data Set I Data Set II Mean is 483.8461538 Median is 400
Mode is 300
Data Set II
Mean is 474
Median is 350
Data Set II

7. Five Number Summary Used to construct a box-and-whisker plot Minimum
Quartile 1 (Q1) – median of the lower data points
Median
Quartile 3 (Q3) – median of the upper data points
Maximum

8. Example 2
Use this set of data to make a box-and-whisker plot: 59, 27, 18, 78, 61, 91, 52, 34, 54, 93, 100, 87, 85, 82, 68 STEP 1: Write the numbers in numerical order, from smallest to greatest.

9. STEP 2: Create a five number summary.
Minimum:
Quartile 1:
Median:
Quartile 3:
Max:

10. STEP 3: Construct and box-and-whisker plot.
Minimum:
Quartile 1:
Median:
Quartile 3:
Max:

11. Example 3: You try!
Use the following data set to create a five number summary and construct the box-and-whisker plot.
87, 7, 41, 50, 15, 220, 23, 99, 11, 45, 11, 61, 3, 39, 21

12. Solution
Minimum: 3
Q1: 11
Median: 39
Q3: 61
Maximum: 220