Mean, Median, and Mode

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Mean, Median and Mode

• Mean, Median, and Mode

Measures of Central Tendency
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Mean, Median and Mode
What is the mean?

• Mean, Median, and Mode

The SUM of the data, divided by the number of
items in the set of data .. commonly called
the average.
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Mean, Median and Mode
What is the mode?

• Mean, Median, and Mode

The data item that appears the MOST
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Mean, Median and Mode
What if the data all appear the same number of
times? 1,1,2,2,3,3,4,4

• Mean, Median, and Mode

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1,1,2,2,3,3,4,4

• Mean, Median, and Mode

There is NO mode
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Can there be more than one mode?
1,2,2,3,4,4,5,6,7

• Mean, Median, and Mode

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1,2,2,3,4,4,5,6,7
Yes, there are two modes. What are they?

• Mean, Median, and Mode

2 and 4
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Mean, Median and Mode
What is the median?

• Mean, Median, and Mode

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What is the median?
The middle number in the set of data when written
in order (first step we do)
Given 2,14,28,0,1,1 Reorder from least to
greatest 0,1,1,14,28 The middle number is 1

• Mean, Median, and Mode

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What if you have an even set of numbers?
Given 10, 0, 20, 30 Reorder from least to
greatest 0,10, 20, 30 Add the two middle
numbers together.

• Mean, Median, and Mode

Divide by 2. What is your median?
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Mean, Median and Mode
Which will an outlier affect the most the mean,
median or mode? (Hint Think of class test scores
What is an outlier?

• Mean, Median, and Mode

A data item that is far apart from the rest of
the data items
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Mean, Median and Mode
What is the range?

• Mean, Median, and Mode

The difference between the largest and smallest
data values
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Step 1 Rewrite in order from least to greatest
Mean, Median and Mode
Lets try one

• Mean, Median, and Mode

2, 1, 0, 1, 5, 3, 4, 2, 0, 3, 1, 2
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Mean, Median and Mode
Mean 2 Range 5 Median 2
Mode 1 and 2

• Mean, Median, and Mode

2, 1, 0, 1, 5, 3, 4, 2, 0, 3, 1, 2
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Mean, Median and Mode
Test scores in an Algebra class 99, 85, 80, 25,
99, 100
What is the mean, median, mode and range?

• Mean, Median, and Mode

Mean 81.3 Median 92 Mode 99 Range 75
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Mean, Median and Mode
Write a paragraph about what would be your most
useful indicator of central tendency in this
case You are ordering a small number of shoes
for your shoe store based on the sales of sizes
from last year. Write why you made your
selection. Why did you not choose the other two?

• Mean, Median, and Mode