You need:pg. 121 on board asappen/pencilcomposition notebookcalculatorACT Aspire Bell Ringer Question:

Unit 8: Day 3Box and Whisker PlotsMs. Hall

Too bad this is not a box and whisker plot, but it is a great way to remember it!

What’s the big deal about it? Box and Whisker Plot: a graphic way to

display the median, quartiles, and extremes of a data set on a number line to show the distribution of the data.

You can show all the important values. Quartiles are the values that divide a list

of numbers into quarters (4 parts kind of like quadrants on a graph).

You need five values in order to draw the box and whisker plot. It’s called “the five number summary”.

The first step is to put the numbers in ascending order from least to greatest.

The second step is to find the median of the entire set (this is quartile 2).

The third step is to find the medians of the two halves (this makes up quartile 1 and 3).

The final step is find the minimum and maximum of the entire set.

The Five Number Summary

Example 1 2,5,6,6,8,10,11,12,14 (Find the five number summary)

1.The first step is to put the numbers in ascending order from least to greatest.2.The second step is to find the median of the entire set (this is quartile 2).3.The third step is to find the medians of the two halves (this makes up quartile 1 and 3).4.The final step is find the minimum and maximum of the entire set.

Now, we can draw! You want to draw a number line that goes a little

above and below your data and label your line with numbers.

Next, you want to draw five small lines or tally marks to represent the five number summary.

The “box” is represent from Q1 to Q3. The “whiskers” are drawn to the minimum and

maximum.

2 5 6 6 8 10 11 12 14 5.5 8 11.52 Q1 Q2 Q3 14

Interquartile Range The interquartile range is from Q1 to Q3:

Interquartile Range or IQR = Q3 – Q1 The interquartile range helps detect outliers

which will be talked about in later math classes.

25% 25% 25% 25%Q1 Q2 Q3

Example 2 Mrs. Sparrow gave her students a math test. Here are

their test scores:85,66,99,80,93,85,78,43,75,96,68,72,82,88,95,90Draw a box and whisker plot. Find the interquartile range (IQR).

43, 66, 68, 72, 75, 78, 80, 82, 85, 85, 90, 93, 95, 96, 99Q2Q1 Q3

40 42 44 46 48 50 52 54 56 58 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 100Q1 Q2 Q3

Min

Min

Max

Max

IQR = Q3 – Q1 = 93 – 72 = 21

1.The first step is to put the numbers in ascending order from least to greatest.2.The second step is to find the median of the entire set (this is quartile 2).3.The third step is to find the medians of the two halves (this makes up quartile 1 and 3).4.The final step is find the minimum and maximum of the entire set.

Now it’s your turn to try it on your own.

Homework Problem:

pg. 740 #9

Now it’s your turn to try it on your own.

Homework Problem:

You and your pod group are to pick one part of data from the room around you. You need to do the five number summary as well as the IQR for that data. But first, pick your data then write all the numbers down so you can work on it at home if you don’t finish in class.

Now it’s your turn to try it on your own.

Homework Problem:

Easter Egg HuntSuppose 15 kids go to a local Easter egg hunt. Here are the number of eggs they found: 10, 16, 8, 12, 5, 30, 13, 14, 27, 7, 15, 12, 17, 9, 10

1. Find the five number summary and IQR of the eggs.  2. Now, the kid, who got 14 treats, noticed some leftover eggs as she was walking back which brings her total up to 19 eggs. Does her new total change any of the five number summary or the interquartile range?