Constructing a Frequency Distribution

1.   Choose either individual data points or four to eight evenly spaced intervals (if there are several different values).

2.  Tally the number of data point or each individual point or in each interval.

3.  List the frequency of each individual data point or interval.

4.  Find the relative frequency of each data point (or interval) by dividing the relative frequency by the total number of data points.

Possible Classroom Examples:

• In order to study the composition of families in Manistee, Michigan, 40 randomly selected married couples were surveyed to determine the number of children in each family. The following results were obtained.

2	1	3	0	1	0	2	5	1	2	0	2	2	1
4	3	1	1	3	4	1	1	0	2	0	0	2	2
1	0	3	1	1	3	4	2	1	4	0	1

• Organize the given data by creating frequency distribution.
• Construct a histogram to represent the data.

• The weights, in pounds, of 35 packages of ground beef at the Cut Above Market were as follows:

1.0	1.9	2.5	1.2	2.0	0.7	1.3	2.4	1.1
3.3	2.4	0.8	2.3	1.7	1.0	2.8	1.4	3.0
0.9	1.1	1.4	2.2	1.5	3.2	2.1	2.7	1.8
1.6	2.3	2.6	1.3	2.9	1.9	1.2	0.5

• Organize the given data by creating a frequency distribution. (Group the data into six intervals.)
• Construct a histogram to represent the data.

• In order to examine the effects of a new registration system, a campus newspaper asked freshmen how long they had to wait in a registration line. The frequency distribution below summarizes the responses. Construct a histogram to represent the data.

x = time in minutes	number of freshman
	101
	237
	169
	79
	51
	63

• The frequency distribution below lists the number of hours per day that a randomly selected sample of teenagers spent watching television. Where possible, determine what percent of the teenagers spent the following number of hours watching television.

x = hours per day	frequency
	23
	45
	53
	31
	17

• less than 4 hours
• not less that 6 hours
• at least 2 hours
• less than 2 hours
• at least 4 hours but less than 8 hours
• more than 3.5 hours