FREQUENCY TABLES, LINE
PLOTS, & HISTOGRAMS
TERMS
Frequency  number of times that
something happens
**The key here is that frequency is always
about the NUMBER of times
Frequency table  a table that shows the
frequencies of items
EXAMPLE 1
A number cube was
rolled 20 times. The
results were:
Make a frequency table
of this data.
2
6
5
6
3
4
1
1
6
5
4
4
1
3
2
3
2
2
5
3
EXAMPLE 1
2
4
4
3
6
1
4
2
5
6
1
2
6
6
3
5
Number
Tally
Frequency
1
II
2
2
IIII
4
3
IIII
4
4
III
3
5
III
3
6
IIII
4
3
5
2
3
LINE PLOT
To make a line plot:
1. Draw a number line that includes all the
values (in example 1 this was
1,2,3,4,5,6)
2. Place an “X” above each number to
indicate the number of times it occurs.
Number
Tally
Frequency
1
II
2
2
IIII
4
3
IIII
4
4
III
3
5
III
3
6
IIII
4
X
X
X X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
1
3
4
5
6
2
HISTOGRAM
A graph that shows the frequencies of the
data
**Looks like a bar graph.
EXAMPLE 2
The number incorrect on the latest quiz in
Mr. Marvel’s algebra class
4 1
7 0
10 5
2 3
2 2 1 1 9 1
3 1 0 4 8 4
EXAMPLE 2
4 1
7 0
10
2
5
3
2 2 1 1 9 1
3 1 0 4 8 4
1. Decide on an interval size (starts with 0
goes to 10)
Interval size: 2
EXAMPLE 2
4 1
7 0
10
2
5
3
2 2 1 1 9 1
3 1 0 4 8 4
1. Decide on an interval size (starts with 0
goes to 10)
Interval size: 2
2. Make a frequency table
EXAMPLE 2
4
7
1
0
10
2
5
3
2 2 1 1 9 1
3 1 0 4 8 4
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Frequency for the
Number Incorrect
5
Frequency
0–1
2–3
4–5
6–7
Number Incorrect
8–9
10 - 11
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Frequency for the
Number Incorrect
5
Frequency
0–1
2–3
4–5
6–7
Number Incorrect
8–9
10 - 11
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Frequency for the
Number Incorrect
5
Frequency
0–1
2–3
4–5
6–7
Number Incorrect
8–9
10 - 11
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Frequency for the
Number Incorrect
5
Frequency
0–1
2–3
4–5
6–7
Number Incorrect
8–9
10 - 11
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Frequency for the
Number Incorrect
5
Frequency
0–1
2–3
4–5
6–7
Number Incorrect
8–9
10 - 11
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Frequency for the
Number Incorrect
5
Frequency
0–1
2–3
4–5
6–7
Number Incorrect
8–9
10 - 11
Number
Incorrect
Tally
Frequency
0–1
IIII II
7
2–3
IIII
5
4–5
IIII
4
6–7
I
1
8–9
II
2
10 - 11
I
1
Frequency for the
Number Incorrect
5
Frequency
0–1
2–3
4–5
6–7
Number Incorrect
8–9
10 - 11
Assignment
12.1: 1 – 17, 20 - 23