Download Mean, Median, and Mode

Mean, Median, and Mode
Definitions:
Mean: the average of a group of numbers
Median: is the middle number when the numbers are arranged in ascending (up) or
descending (down) order.
Mode: the number that occurs most often. There can be more than one mode.
Range: The difference between the highest and lowest number.
Rules for Calculating the mean:
1. Add up all of the numbers
2. Divide by the total number of numbers used in the question.
Example:
Find the mean of the following numbers: 7, 5, 1, 4, 3
7+5+1+4+3
5
= 20
5
= 4
Rules for Finding the Median:
1. Arrange then numbers in ascending (from smallest to largest) or descending (from
largest to smallest) order.
2. If there is an odd number of numbers then the median is the middle number.
3. If there is an even number of numbers, then you must find the average of the 2 middle
numbers. The average of these numbers is the median.
Examples:
Find the median for each of the following:
1. 7, 6, 9, 5, 10
ascending order
5, 6, 7, 9, 10
The middle number (median) is 7
2. 3, 8, 5, 9, 7, 4
descending order
9, 8, 7, 5, 4, 3
The 2 middle numbers are 7 and 5. The average of these two numbers is:
7+5
2
= 12
2
= 6
The median is 6.
Rules for Finding the Mode
1. Simply write down the number or numbers that occur the most.
Examples:
1. 6, 9, 5, 6, 8, 7
The number 6 occurs more often than the other numbers
The mode is 6.
2. 10, 11, 9, 11, 8, 9, 7
The numbers 9 and 11 occur more often than the other numbers.
The modes are 9 and 11