1. Teacher Notes This is a two day lesson. The Homework is not split up over the two days, but could be at your discretion. Students should have two days to do it. Get as far as you can on day 1, and do the rest on day 2.

2. Quick Start Expectations 1.Fill in planner and HWRS HW: p. 22, #9-16 (DUE THURSDAY) 2.Get a signature on HWRS 3.On desk: calculator, journal, HWRS, pencil, pen, 4.Switch to CC7 Books; clean up from yesterday, please! 5.TAKE OUT JOURNALS: Title Today’s Notes “Exploring Quartiles” What do you think quartiles are?

3. Exploring Quartiles DriverYearSpeed (MPH) Arie Luyendyk1990185 Rick Mears1991176 Bobby Rahal1986170 Juan Montoya2000167 Emerson Fittipaldi1989167 Helio Castronoves2002166 Rick Mears1984163 Mark Donahue1972162 Al Unser1987162 Tom Sneva1983162 Fastest winning speeds of the Indy 500

4. Finding the Inter-quartile Range (IQR) Step 1: Write the speeds in order from least to greatest. 162, 162, 162, 163, 166, 167, 167, 170, 176, 185 Step 2: Find the median of the data since the median separates the data into two halves. 162, 162, 162, 163, 166, 167, 167, 170, 176, 185 Since there are two numbers in the middle we have to find the mean of the two. (166 + 167) / 2 = 166.5

5. Steps Continued… Step 3: Find the median of the upper half of the numbers________. This number is called the upper quartile. Circle this number in your step 1 and label it UQ Step 4: Find the median of the lower half of the numbers_______. This number is called the lower quartile. Circle this number in your step 1 and label it LQ 170 162 162, 162, 162, 163, 166, 167, 167, 170, 176, 185

6. Steps Continued… Step 5: The middle half of the data goes from the upper quartile (UQ) to the lower quartile (LQ). Subtract the LQ from the UQ. 170 – 162 = 8 This is called the inter-quartile range of the scores!! The IQR describes the variability of the middle 50% of the data values. 162, 162, 162, 163, 166, 167, 167, 170, 176, 185

7. More Practice! Roller Coaster Name/Location Year Opened Speed (MPH) Kingda Ka, Six Flags NJ 2005128 Top Thrill Dragster, Cedar Point OH 2003120 Dodonpa, Japan 2001112 Superman, Six Flags CA 1997100 Tower of Terror, Australia 1997100 Steel Dragon, Japan 200095 Millennium Force, Cedar Point OH 200093 Goliath, Six Flags CA 200085 Titan, Six Flags TX 200185 Phantoms Revenge, Kennywood Park 200182 Xcelerator, Knott’s Berry Farm 200282 Fujiyama, Japan 199681 Thunder Dolphin, Japan 200381

8. Find the Stats… Step 1: Order the data… 81, 81, 82, 82, 85, 85, 93, 95, 100, 100, 112, 120, 128 Range: 128 – 81 = 47 Median: 93 Upper Quarter (UQ): (100 + 112)/2 = 106 Lower Quartile (LQ): 82 Interquartile Range: 106 – 82 = 24 Mean: about 96 Mode: No mode because 81, 82, 85, 100 each appear twice Outliers: 128

9. P. 16

10. Use on tonight’s HW!

12. How might you decide which are faster, steel-frame roller coasters or wood-frame roller coasters?

15. Range = 68 mi/h Range = 41 mi/h Mean = 55.03 mi/h Mean = 52.6 mi/h

16. Median = 54.5 mi/h Median = 53 mi/h IQR = 28 mi/h IQR = 10 mi/h Comparisons on next slide…

17. IQR for steel-frame is more than twice the IQR for the wood-frame The median of the steel-frame is greater than the median of the wood-frame The middle 50% of the speeds for steel- frame are more variable than the middle 50% for wood-frame

19. Box-and-Whisker Plots At least 25% of the steel-frame coasters have speeds that are faster than those of wood-frame coasters.

20. The measures of center for steel-frame and wood- frame coasters are somewhat similar. Speeds of steel-frame coasters vary greatly. Measures of spread (specifically IQR) show that at least 25% of the steel-frame coasters have speeds that are faster than those of wood-frame coasters.