Frequency Table
In short: Frequency table is a table that lists each data value or interval next to a count of how many times it occurs, with the counts adding up to the total.
6th GradeStatistics6.SP.B.4
What is Frequency Table?
A frequency table turns a messy list of numbers into a tidy tally. Each row names a value or an interval and records its frequency, the number of times that value appears in the data.
Precisely, the frequencies must add up to the total number of data values. A relative frequency divides each count by that total, and the cumulative version adds counts row by row from the top.
How to spot it
- A raw list of survey answers needs to be organized before graphing.
- A table has a column of values and a second column of counts or tally marks.
- A question asks how many data values equal a certain number or lie in a certain range.
- You must find a total by adding counts, or find a part-of-whole by dividing a count by the total.
The method
- List every distinct value, or every equal-width interval, in the first column.
- Go through the data once and make a tally mark in the row of each value.
- Convert tally marks to numbers in the frequency column.
- Add the frequencies and check that the total equals the number of data values.
Frequency Table: solved example
Problem
The table above counts siblings for 25 students at a middle school in Tacoma. How many students have at least 2 siblings, and what fraction of the class is that?
Solution
Add the rows for 2, 3 and 4 siblings: \(7 + 3 + 2 = 12\) students.
The fraction is \(\frac{12}{25} = 0.48\). So 12 students, or 48%, have at least 2 siblings.
Try it
Question 1
A frequency table shows scores 6 (frequency 3), 7 (frequency 5), 8 (frequency 9), 9 (frequency 3). How many scores are there in all?
Show the answer
\(3 + 5 + 9 + 3 = 20\).
Question 2
In the same table, find the relative frequency of the score 8 as a decimal.
Show the answer
\(\frac{9}{20} = 0.45\).
Frequency Table vs. Histogram
A frequency table is the counts in table form. A histogram is the picture of those counts for numerical intervals. You usually build the first, then draw the second from it.
Keep going
Lessons
Worksheets and quizzes
Related words
Whole dictionary: A–Z · 6th Grade · Statistics