Stem-and-Leaf Plots

question: How many swimmers were younger then 30

Stem - - Leaf

0

1 - - 1

2 - - 3,9

3 - -

4 - - 7

5 - - 5,7,7,9

6 - - 5,5,6,6,7,8,9

7 - - 0,1

Key: 7 - - 1 means 71

We are looking for any swimmer's whose age begins with a 0, 1 or 2.

We look at the tree and count one swimmer (age 11) beginning with a 1 and two swimmers (age 23 and 29) beginning with a two.

In total, there are three swimmers younger than 30.

In total, there are 3 swimmers that are younger than 30.