Download Mean, Median and Mode Reference Sheet

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Mean, Median and Mode Reference Sheet
When analyzing data knowing the average is very beneficial. There are several ways to calculate
the average. There are three types of averages: mean, median and mode.
Mean- One type of average is called the mean. Pay special attention to finding the mean since
this is sometimes repeated in finding the median. The mean or numerical average is calculated
by adding up all of the numbers and then dividing by the total number of items in the list.
There are two steps to finding the mean.
For Example:
1. Add up the numbers.
75
62
85
+ 90
312
2. Take the total (312) and divide it by 4.
Divide by 4 because four numbers were
added up in step one. If nine numbers were
added up in step one, you would divide by
nine instead of four. Once we have divided
312 by 4, we get 78. The mean is 78.
____78
4) 312
Median- To find the median, we need to get the middle number in a set of data. To find the
median, place all the numbers in order from least to greatest. If the ordered list has an odd
number of entries, the median is the middle number in the list. If the list has an even number of
entries, the median is found by adding the two center numbers together and dividing by two.
Odd amount of numbers:
12, 78, 46, 92, 100
1. Put them in order
12, 46, 78, 92, 100
2. Find the center number
12, 46, 78, 92, 100
78 is the median
Even amount of numbers:
31, 51, 18, 100, 97, 71
1. Put in order:
18, 31, 51, 71, 97, 100
2. Find the middle number:
18, 31, 51, 71, 97, 100
3. Find the mean of the middle numbers:
51 + 71 = 122
122 = 61
2
61 is the median
Mode-The mode is the number that appears most often in a list of numbers. In the following
sequence, the number 12 will be the mode.
9, 12, 18, 24, 36, 12, 5