Section 12.2- Frequency and Histograms
Essential Question: Why is it important to organize data concisely?
Do Now:
Be sure to explain how you arrived at your estimate!
What is a Frequency Table?

Organizes a set of values into ____________________ and shows the
_________________ for each

____________________ do NOT ______________, do NOT have any _________
and are of ____________ ____________
Example of a Frequency Table
Hours of Sleep Students Get Per
Frequency
Night
0-2
1
3-5
3
6-8
10
9-11
2
Example 1: Making a Frequency Table
The numbers of home runs by the batters in a local home run derby are listed below.
What is a frequency table that represents the data? Use intervals of 5.
7 17 14 2 7 9 5 12 3 10 4 12 7 15
What is a Histogram?

Similar to a ________ ___________

Display information from a _________________ _________

There are ________ _____________ between the __________
Example 2: Making a Histogram
The finishing times, in seconds, for a race are shown below. What is a histogram that
represents the data?
95 105 83 80 93 98 102 99 82 89 90 82 89
Shapes of Histograms
Example 3: Interpreting Histograms
The following set of data shows the numbers of dollars Jay spent on lunch over the last
two weeks. Make a histogram of the data. Is the histogram uniform, symmetric or
skewed?
17 1 4 11 14 14 5 16 6 5 9 10 13 9
a.
b. How would you describe the histogram?
c. How much money should Jay plan to bring for lunch next week? Explain your
reasoning.
Example 4: Making a Cumulative Frequency Table
What is a cumulative frequency table that represents the data below?
12 13 15 1 5 7 10 9 2 2 7 11 2 1 0 15
Fill in the three columns below.
Individual or Group Work
Create a histogram to model something that you are interested in. For example, you can
use the points scored by your favorite basketball team over their last 20 games or the
length of each song on your favorite artist’s newest album. Create a rough draft on the
paper and ask Mr. Thai to get a piece of graph paper and construction paper to create
your own histogram. Those who complete a histogram will receive EXTRA CREDIT on
the last test of the marking period on statistics!
HW: p. 736 #22-30 all