Stem and Leaf Plots

Date: 2/3/96 at 11:18:56
From: Anonymous
Subject: Stem and leaf plot problem

Dear Dr. Math,

I am in the Math Counts math competition, and when doing practice 
problems we came across this problem:

Use the stem-and-leaf plot of the recent art project scores to 
find the mean score.  Express as a decimal.

5 | 0 0
4 | 9 7 3 3 1
3 | 8 7
2 | 9

What in the world is a stem-and-leaf plot?  Thank you very much,

Molly Richman, Age 12  Grade 8
Homeschooled

Date: 6/19/96 at 14:39:33
From: Doctor Robert
Subject: Re: Stem and leaf plot problem

Stem and leaf plots are a way that statistician can look at the 
distribution of numbers given to them to analyze.  For example, in 
the stem-and-leaf plot you show, there were two scores in the 50's 
(They were both 50), 5 scores in the forties (49,47,43,43,41), two 
scores in the thirties (38,37) and one score in the twenties (29).  
So all of the art scores were 50, 50, 49, 47, 43, 43, 41, 38, 37, 
and 29.  You can find the average score by adding them and 
dividing by 10.

-Doctor Robert,  The Math Forum