Mean and Median
Math
MEAN
• The mean is a synonym for average.
MEAN
• To find the mean (average) of a group of numbers the first step is to add all of the numbers.
Example: 4, 10, 3, 7, 2, 10
4 + 10 + 3 + 7 + 2 + 10 = 36
MEAN
• After you have added all of the numbers, the next step is to divide the sum by the total number of addends.
• Example:
36/6 = 6
• Mean = 6
MEAN
• Note: sometimes, you do not get a whole number.
MEAN
• Now, you try one!
• 7, 9, 11, 6, 13, 6, 6, 3, 11
• What is the first step?
MEAN
• 7 + 9 + 11 + 6 + 13 + 6 + 6 + 3 + 11 = 72
• What is the next step?
MEAN
• Divide• 72/9 = 8• Mean = 8• Now, let’s try 1 more!
MEAN
•Find the mean for this group of numbers.
•11, 10, 24, 16, 14
MEAN
•11 + 10 + 24 + 16 + 14 = 75
MEAN
•75/5 = 15
•Mean = 15
MEDIAN
• The median is the middle number or value.
• To find the median the first step is to put the numbers in order from least to greatest.
MEDIAN
• The number in the middle of the list is the median.
MEDIAN
• 4, 23, 16, 17, 6, 10, 20
• Put the numbers in order from least to greatest.
MEDIAN
• 4, 6, 10, 16, 17, 20, 23
• Median = 16
MEDIAN
•Now you try one!
•What is the median of
5, 11, 23, 9, 10
MEDIAN
•5, 9, 10, 11, 23
•Median = 10
MEDIAN• 6, 3, 7, 6, 11, 13, 6, 11, 9
• Put the numbers in order from least to greatest.
MEDIAN
•3, 6, 6, 6,
7, 9, 11, 11, 13
•Median = 7
MEDIAN
• If there are two middle values, the median is halfway between them.
MEDIAN• 13, 7, 6, 8, 6, 3, 11, 6, 11, 9
• Put the numbers in order
MEDIAN
•3, 6, 6, 6, 7, 8, 9, 11, 11, 13
• There are two middle numbers or values, 7 and 8. The median is halfway between 7 and 8. The median is 7 ½ or 7.5.