6th Grade Math Textbook, Progress

Histograms

9-13

Heights of Ms. Eilhardt’s

Students (in inches)

52 57 59 59 50 59

51 52 49 60 56 50

55 58 53 52 51 54

50 54 53 58 57 67

55 57 58 56 57 58

49–52 9

53–56 8

57–60 12

61–64 0

65–68 1

Height (in.) Tally Frequency

Since the data span from 49 to 67,

use 5 intervals of 4 inches.

A broken scale is used

since the data start at 49.

49 –52 53–56 57–60 61–64 65–68

Heights in Inches

12

10

8

6

4

2

0

Number ofStudents

Heights of Ms. Eilhardt’s Students

Ms. Eilhardt organized the data shown at the right.

First she made a frequency table.

To make a frequency table:


Choose a reasonable interval to

group the data.

Tally the data for each interval and

record the frequencies.

Then Ms. Eilhardt made a histogram from the

same table. A histogram is a graph that shows

the frequencyof equal intervals of data. In a

histogram, the intervals must not overlap.

There are no spaces between the bars of a

histogram, unless there is an interval with a

frequency of 0.

To make a histogram:


Use the frequency table

to choose and label a

scale on the vertical axis

for the frequencies.


Label the horizontal axis,

listing the intervals in order.


Draw bars (with no

space between them) to

show the frequency of

each interval.


Write a title for the histogram.

In which height group are most of Ms. Eilhardt’s students?

To find which group, look for the tallest bar and

read the interval it represents.

Most of Ms. Eilhardt’s students are from 57–60 inches tall.

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