Discrete Math Section 17.2 Represent data using a box and whisker plot. A box and whisker plot is a method for dividing a set of data into four parts called quartiles. Lower extreme – smallest value of a set of data Upper extreme – largest value of a set of data Lower quartile – median of the items less than the median Upper quartile – the median of the items greater than the median Box – extends from the lower to the upper quartiles Whiskers – extend from the quartiles to the extremes Range – the difference from between the extremes Interquartile range – difference between the quartiles Outliers – any data item whose distance to the nearer quartile exceeds 1.5 times the interquartile range

example The ages of the 1st 41 presidents at the time they took office expressed as a stem and leaf plot 4 | 3 4 7 8 9 5 | 0 0 0 1 1 1 1 2 2 3 4 5 5 5 5 6 6 6 6 7 7 7 8 8 8 9 6 | 1 1 2 2 3 5 5 6 8 7 | 0 Find the extremes Find the median and the lower and upper quartiles Find the interquartile range Are there any outliers? Draw a box and whisker plot of the data

example Consider the sets of score from two different algebra classes 1st class 72,74,78,78,80,81,85,87,88,90,91,92,96,98,99,99 2nd class 60,64,65,69,70,73,74,78,81,82,84,90 Express the data in back to back stem and leaf plots with 8 stems Express the data using 2 box and whisker plots

Use a graphics calculator to represent the data Calculator exercises Use a graphics calculator to represent the data 3,6,12,8,4,9,12,7,9,14,9,2,9,3,11,10,14,2,35 Using measures of central tendencies Using a box and whisker plot

Assignment page 651 problems 2,3,4,6,7