Box-and-Whisker Plots Percentages
Ok in this problem:
Ok first I know that
- Each small box is 25%, and the box combining the two boxes is 50%
- Each whisker is 25%
I have two questions:
1) What if they ask you "What percent of the data is less than 64?" I am confused because there isn't a whisker around the area of the less than 64. All I know is that all the data (whiskers + boxes) has to be 100%
2) What if they ask you "What percent of the data is less than 66 and 92?" How would I divide the boxes or something to get the percentage?
(Sorry the image is big, I wasn't able to get to Photoshop right now)
Think very hard on what "no whisker" means. There is a reason why they asked "greater than 64" and NOT "greater than or equal to 64". What's the difference?
The answer to "less than 64" is zero (0)! Why? There is a mass of 25% of your probability AT 64.
This is a good reason why there are many ways to represent data graphically. Each way has its own merits. This is one feature that may seem a little confusing with box and whisker.
On the other hand, it may be just a typo and there should be a whisker.