Download MEAN, MEDIAN, MODE, AND RANGE STUDy GUIDE

Mean, Median, Mode, and
Range Study Guide
SOLs:
Name: ________KEY_____________
Homeroom: _______________________
5.15 The student, given a problem situation, will collect, organize, and interpret data in a variety of
forms, using stem-and-leaf plots and line graphs.
5.16 a) The student will describe mean, median, and mode as measures of center
b) describe mean as fair share
c) find the mean, median, mode, and range of a set of data
d) describe the range of a set of data as a measure of variation
13
17
7
20
19
Mean –“the average”
1. Find the sum of all the numbers
2. Divide by the number of addends
Median –“the middle”
1. Arrange the numbers in order from
least to greatest
2. Find the middle number
*If there is an even number of numbers,
add the middle numbers and divide by two
7
11
6
8
13 + 17 +7 + 20 + 19 + 7 + 11 +6 +8 = 108
108 ÷ 9 = 12
6, 7, 7, 8, 11, 13, 17, 19, 20
6, 7, 7, 8, 11, 13, 17, 19, 20
Mode –“most often”
1. Arrange the numbers in order from
6, 7, 7, 8, 11, 13, 17, 19, 20
least to greatest
2. Find the number that occurs most often 6, 7, 7, 8, 11, 13, 17, 19, 20
*Sometimes there may be more than one mode
Range –“the difference between the
highest and lowest numbers”
1. Subtract the least number from the
greatest number
20 – 6 = 14
Stem & Leaf Plots –A way of organizing data.
The tens digit in each
number is a “stem.”
Stem
Leaf
1
2, 6, 6
2
2, 5
3
1, 8
4
2, 9
5
0
12
25
38
16
42
49
22
16
50
31
The ones digit in each
number is a “leaf.”
Your turn! Create a stem & leaf plot based on the data in the box. Then answer the questions.
Stem
Leaves
13
21
10
1
0, 2, 3, 8
36
12
22
2
2, 2
3
6, 6
4
1, 2
5
7
36
42
1) What is the range of the data? _________47_______________________
2) What is the mean of the data? _________28_______________________
3) What is the mode of the data? _________36_______________________
4) What is the median of the data? ________22_______________________
57
41
18