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Measures of Central Tendency. Mean, Median, Mode, Range. Jan Sands 2007. Definition of Mean. Mean Means Average. Definition of Mean. Mean – the average of a group of numbers. 2, 5, 2, 1, 5. Mean = 3. Mean is found by evening out the numbers. 2, 5, 2, 1, 5.
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Measures ofCentral Tendency Mean, Median, Mode, Range Jan Sands 2007
Definition of Mean Mean Means Average
Definition of Mean • Mean – the average of a group of numbers. 2, 5, 2, 1, 5 Mean = 3
Mean is found by evening out the numbers. 2, 5, 2, 1, 5
Mean is found by evening out the numbers. 2, 5, 2, 1, 5 mean = 3
How to Find the Mean of a Group of Numbers • Step 1 – Add all the numbers. 2, 5, 2, 1, 5 2+ 5+ 2+ 1+ 5 = 15
How to Find the Mean of a Group of Numbers • Step 2 – Divide the sum by the number of items. 2, 5, 2, 1, 5 How many total items are there?
How to Find the Mean of a Group of Numbers • Step 2 – Divide the sum by the number of items. 15 ÷ 5 = 3 sum number of items mean
Find the Mean of a Group of Numbers The mean or average of these numbers is 3. 2, 5, 2, 1, 5
What is the mean of these numbers? 7, 10, 16 The mean is 11.
What is the mean of these numbers? 2, 9, 14, 27 The mean is 13.
What is the mean of these numbers? 1, 2, 7, 11, 19 The mean is 8.
What is the mean of these numbers? 26, 33, 41, 52 The mean is 38.
Definition of Median Median is in the Middle
Definition of Median • Median – the middle number in a set of ordered numbers. 1, 3, 7, 10, 13 The median is 7.
How to Find the Median in a Group of Numbers • Step 1 – Arrange the numbers in order from least to greatest. 21, 18, 24, 19, 27 18, 19, 21, 24, 27
How to Find the Median in a Group of Numbers • Step 2 – Find the middle number. 18, 19, 21, 24, 27 21 is the median number.
What is the median of these numbers? 16, 10, 7 7, 10, 16 The median number is 10.
What is the median of these numbers? 29, 8, 4, 11, 19 4, 8, 11, 19, 29 The median number is 11.
How to Find the Median in a Group of Numbers • Step 3 – If there are two middle numbers, find the mean of these two numbers. 18, 19, 21, 25, 27, 29
How to Find the Median in a Group of Numbers • Step 3 – If there are two middle numbers, find the mean of these two numbers. 21+ 25 = 46 median 46 ÷ 2 = 23
What is the median of these numbers? 31, 7, 2, 12, 14, 19 2, 7, 12, 14, 19, 31 First Step 12 + 14= 26 Second Step 26 ÷ 2 = 13 The median is 13.
What is the median of these numbers? 53, 5, 81, 67, 25, 78 5, 25, 53, 67, 78, 81 First Step 53 + 67= 120 Second Step 120÷ 2 = 60 The median is 60.
Definition of Mode Mode is the most Popular
Definition of Mode • Mode – the number that appears most frequently in a set of numbers. 1, 1, 3, 7, 10, 13 The mode is 1.
How to Find the Mode in a Group of Numbers • Step 1 – Arrange the numbers in order from least to greatest. 21, 18, 24, 19, 18 18, 18, 19, 21, 24
How to Find the Mode in a Group of Numbers • Step 2 – Find the number that is repeated the most. 18, 18, 19, 21, 24 The mode is 18.
Which number is the mode? 29, 8, 4, 8, 19 4, 8, 8, 19, 29 The mode is 8.
Which number is the mode? 1, 2, 2, 9, 9, 4, 9, 10 1, 2, 2, 4, 9, 9, 9, 10 The mode is 9.
Which number is the mode? 22, 21, 27, 31, 21, 32 21, 21, 22, 27, 31, 32 The mode is 21.
Which number is the mode? 52, 21, 37, 31, 28, 42 21, 28, 31, 37, 42, 52 There is no mode.
Which number is the mode? 23, 25, 21, 31, 21, 25 21, 21, 23, 25, 25, 31 There are two modes: 21 and 25.
Definition of Range Range is the distance between the least and greatest values in a set of numbers.
Definition of Range • Range – the difference between the greatest and the least value in a set of numbers. 1, 1, 3, 7, 10, 13 The range is 12.
How to Find the Range in a Group of Numbers • Step 1 – Arrange the numbers in order from least to greatest. 21, 18, 24, 19, 27 18, 19, 21, 24, 27
How to Find the Range in a Group of Numbers • Step 2 – Find the lowest and highest numbers. 21, 18, 24, 19, 27 18, 19, 21, 24, 27
How to Find the Range in a Group of Numbers • Step 3 – Find the difference between these 2 numbers. 18, 19, 21, 24, 27 27 – 18 = 9 The range is 9.
What is the range? 29, 8, 4, 8, 19 4, 8, 8, 19, 29 29 – 4 =25 The range is 25.
What is the range? 22, 21, 27, 31, 21, 32 21, 21, 22, 27, 31, 32 32 – 21 =11 The range is 11.
What is the range? 31, 8, 3, 11, 19 3, 8, 11, 19, 31 31 – 3 =28 The range is 28.
What is the range? 23, 7, 9, 41, 19 7, 9, 19, 23, 41 41 – 7 =34 The range is 34.
Mean, Median, Mode, & Range 15, 19, 22, 25, 6, 15, 17
Mean 15, 19, 22, 25, 6, 15, 17 15 + 19 + 22 + 25 + 6 + 15 + 17 = 119 119 ÷ 7 = 17 The mean is 17.
Median 15, 19, 22, 25, 6, 15, 17 6, 15, 15, 17, 19, 22, 25 The mean is 17.
Mode 15, 19, 22, 25, 6, 15, 17 6, 15, 15, 17, 19, 22, 25 The mode is 15.
Range 15, 19, 22, 25, 6, 15, 17 6, 15, 15, 17, 19, 22, 25 25 – 6 = 19 The range is 19.
Mean, Median, Mode, & Range 1. 28, 6, 9, 7, 14, 6, 5 Find the mean, median, mode and range of… 2. 52, 55, 51, 59, 65, 55, 55 3. 43, 43, 32, 38, 49
Mean, Median, Mode, & Range 1. 29, 6, 9, 7, 15, 6, 5 Answers 1. Mean is 11. 2. Median is 7. 3. Mode is 6. 4. Range is 24.
Mean, Median, Mode, Range - answers continued 2. 52, 55, 51, 59, 65, 55, 55 1. Mean is 56. 2. Median is 55. 3. Mode is 55. 4. Range is 14. 3. 43, 43, 32, 38, 49 1. Mean is 41. 2. Median is 43. 3. Mode is 43. 4. Range is 17.