6th Grade Math Textbook, Fundamentals

 &KDSWHU

8-7

Stem-and-Leaf Plots

Objective To read and make stem-and-leaf plots

The table below shows the number of floors in

certain tall buildings. How would you display that

data in a stem-and-leaf plot?

A is a display that uses the digits of the numbers in a data set
to show how the data are distributed. It condenses and orders the data set to let
you see the values and frequencies. It is especially useful in making a large data
set easier to analyze.

A stem-and-leaf plot is two sets of digits separated by a
vertical line. The “stem” is written to the left of the line,
and the “leaves” are written to the right of the line. Each
digit in a data value that has the least place value is
represented by a leaf. The remaining digit in each data
value is represented by a stem. A stem-and-leaf plot
shows every item in the data.

To make a stem-and-leaf plot:

Order the numbers from least to greatest.

31, 32, 36, 39, 45, 47, 51, 53

Since the numbers in the table range from 31 to 53,

use the tens digits for the stem and the ones digits for

the leaves. Draw a vertical line to separate the stems

from the leaves.

Write the stems in ascending order on the left side

of the line.

To the right of each stem, write the appropriate leaf

digits in ascending order from left to right. Note that

the same leaf digit may appear on different stems.

It will also appear more than once on the same stem

if a number in the data set occurs more than once.

Write a key to show what the stems and leaves represent.

Give the stem-and-leaf plot a title.

stem-and-leaf plot

Building Number of Floors

One Cherry Square 51

Newbanc Center 53

Plaza Tower 45

City Centre 39

TMP Tower 36

Deluxe Suites Hotel 47

One Founders Row 32

Peninsula Plaza 31

Key: 3 | 1 31 floors

Number of Floors in Buildings

Stem Leaves

3 1 2 6 9

4 5 7

5 1 3

tens digits ones digits

Key Concept

Stem-and-Leaf Plots

A stem-and-leaf plot has only the last

digit of each number in the data set as

a leaf. The front-end digit (or group of

digits) is the stem.

Since the numbers in a stem-and-leaf

plot are ordered, this type of display is

convenient in finding the median, the

mode, and the range of a set of data.