Warm-Up Exercises 1.Write the numbers in order from least to greatest. 82, 45, 98, 87, 82, The heights in inches of the basketball players in order are 72, 72, 73, 74, 76, 77, 77, 78. How many heights are over 75 inches? under 75 inches? ANSWER 45, 46, 82, 82, 87, 98 ANSWER 4 ; 4

Example 1 Median: Write the scores in numerical order. 89, 90, 92, 92, 92, 93, 94, 94, 95, 96, 96, 97, 97, 97, 97, 98, 98, 98, 98, 99, 99, 99, 99, 99, 100, 100, 101, 102, 103, 108 SOLUTION Mean: = … + ++ ≈ 97.1 Find Measures of Central Tendency National Basketball Association Team Points Per Game 94, 94, 95, 96, 97, 97, 97, 98, 98, 98, 98, 99, 100, 101, 102 Eastern Conference 89, 90, 92, 92, 92, 93, 96, 97, 99, 99, 99, 99, 100, 103, 108 Western Conference Find the mean, median, and mode(s) of the 30 team scores.

Example 1 Find Measures of Central Tendency Mode: The number that occurs most frequently is 99. The median is between the 15th and 16th numbers. Median 97.5 = =

1.Find the mean, median, and mode of the 15 Eastern Conference scores. ANSWER mean: 97.6 ; median: 98 ; mode: 98 Checkpoint Find Measures of Central Tendency

Example 2 Find Ranges of Data Sets Find the range of the two data sets above. The ranges of the points per game in the two data sets are: SOLUTION Eastern Conference: Range 8 = 94 – 102 = Western Conference: Range 19 = 89 – 108 = National Basketball Association Team Points Per Game 94, 94, 95, 96, 97, 97, 97, 98, 98, 98, 98, 99, 100, 101, 102 Eastern Conference 89, 90, 92, 92, 92, 93, 96, 97, 99, 99, 99, 99, 100, 103, 108 Western Conference

Example 3 Find Lower and Upper Quartiles Find the lower and upper quartile of each set of data. Lower quartile: The median of 10, 15, and 17 is 15. Upper quartile: The median of 18, 20, and 21 is 20. a. 10, 15, 17, 18, 20, 21 b. 31, 33, 33, 35, 36, 39, 40, 41, 41 The values are already in order. The median is between 17 and 18. Each half of the data has three items. SOLUTION a.

Example 3 Find Lower and Upper Quartiles Lower quartile: The median of 31, 33, 33, and 35 is 33. Upper quartile: The median of 39, 40, 41, and 41 is The values are already in order. The median is 36. This value does not belong to either the upper half or the lower half of the data set. So, each half of the data has four items. b.

Checkpoint Find the range, median, lower quartile, and upper quartile of the data set. ANSWER range: 18 ; median: 20 ; lower quartile: 16 ; upper quartile: 24 Find Range, Median, and Lower and Upper Quartiles 2. 11, 15, 16, 16, 17, 20, 24, 24, 24, 27, 29 ANSWER range: 28 ; median: 56 ; lower quartile: 53 ; upper quartile: , 50, 51, 55, 55, 55, 57, 63, 66, 68, 68, 75

Draw a Box-and-Whisker Plot Example 4 The two data sets below show the average number of points per game scored by the teams in the National Basketball Association during the 2005–2006 season. National Basketball Association Team Points Per Game 94, 94, 95, 96, 97, 97, 97, 98, 98, 98, 98, 99, 100, 101, 102 Eastern Conference 89, 90, 92, 92, 92, 93, 96, 97, 99, 99, 99, 99, 100, 103, 108 Western Conference Draw a box-and-whisker plot of the Eastern Conference data set above. How many points per game did Eastern Conference teams normally score in the 2005–2006 season?

Example 4 Draw a Box-and-Whisker Plot SOLUTION STEP 1 The 15 values are already in order. STEP 3 Plot these five numbers below a number line. STEP 2 Find the significant values for this data set. The minimum is 94 and the maximum is 102. The median is 98. The lower quartile is 96 and the upper quartile is 99. STEP 4 Draw the box, the whiskers, and a line segment through the median.

Example 4 Draw a Box-and-Whisker Plot

4.Use your answers to Checkpoint Exercises 2 and 3 to draw box-and-whisker plots of each data set. Checkpoint Draw Box-and-Whisker Plots ANSWER Ex. 2 Ex. 3

Checkpoint Draw a box-and-whisker plot of the Western Conference data below. How do the scores for the Western Conference teams compare to those for the Eastern Conference teams? 5. Draw Box-and-Whisker Plots National Basketball Association Team Points Per Game 94, 94, 95, 96, 97, 97, 97, 98, 98, 98, 98, 99, 100, 101, 102 Eastern Conference 89, 90, 92, 92, 92, 93, 96, 97, 99, 99, 99, 99, 100, 103, 108 Western Conference

Checkpoint Sample answer: The Western Conference scores are more spread out than the Eastern Conference scores. Also, the median scores for the Eastern and Western Conferences were very close while the upper quartile was the same for both conferences. Draw Box-and-Whisker Plots ANSWER