Mean, Median, Mode and Range

- The Basics of Statistics

Did You Know

- That you probably use Statistics such as Mean,

Median, Mode and Range almost every day without

even realizing it?!?

Today We Will Learn

- Mean
- Median
- Mode
- Range
- And how to use these in everyday life, as well as

the classroom!

To Help You Learn

- You should have a Pencil, a Piece of Paper, and a

Calculator if you need one.

What Do We Already Know?

- Sure, the words Mean, Median, Mode and Range

all sound confusing - But what about the words we already know, like

Average, Middle, Most Frequent, and Difference? - They are all the same ideas!

Mean

- The mean is the Average of a group of numbers
- It is helpful to know the mean because then you

can see which numbers are above and below the

mean - It is very easy to find!

Mean Example

- Here is an example test scores for Ms. Maths

class. - 82 93 86 97 82
- To find the Mean, first you must add up all of

the numbers. - 8293869782 433
- Now, since there are 5 test scores, we will next

divide the sum by 5. - 4405 88
- The Mean is 88!

Median

- The Median is the middle value on the list.
- The first step is always to put the numbers in

order.

Median Example

- First, lets examine these five test scores.
- 78 93 86 97 79
- We need to put them in order.
- 78 79 86 93 97
- The number in the middle is 86
- 78 79 86 93 97
- In this case, the Median is 86!

Median Example 2

- Now, lets try it with an even number of test

scores. - 92 86 94 83 72 88
- First, we will put them in order
- 72 83 86 88 92 94
- This time, there are two numbers in the middle,

86 and 88 - 72 83 86 88 92 94
- Now we will need to find the Average of these two

numbers, by adding them and dividing by two. - 8688 174 1742 87
- Here the Median is 87

Mode

- The Mode refers to the number that occurs the

most frequently. - Its easy to remember the first two numbers are

the same! MOde and MOst Frequently!

Mode Example

- Here is an list of temperatures for one week.
- Mon. Tues. Wed. Thurs. Fri. Sat.

Sun. - 77 79 83 77 83

77 82 - Again, We will put them in order.
- 77 77 77 79 82 83 83
- 77 is the most frequent number, so the mode 77

Range

- The range is the difference between the highest

and the lowest numbers of the series. - All we have to do is put the numbers in order and

subtract!

Range Example

- Lets look at the temperatures again.
- 77 77 77 79 82 83 83
- The highest number is 83, and the lowest is 77.
- All you need to do is subtract!
- 83-77 6
- In this case, the Range is 6

__ __ __ _

Now YOU try it!!!

This is the Stat Family!

Dad Mom Jack Alex Katie 34 33 5 5

1

Mean

- Here are the ages again
- Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1
- What is the Mean?
- Remember Mean is the AVERAGE
- Try it on your paper and see what you come up

with!

Mean

- Remember, to find the mean, we have to first add

up all of the numbers. - 3433551 80
- Then, since there are 6 people in the family, we

next divide by 6. - 786 13
- The Mean in this case is 13

Median

- Here are the ages again
- Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1
- What is the Median?
- Remember Median is the MIDDLE NUMBER
- Try it on your paper and see what you come up

with!

Median

- Remember, to find the mean, we have to first put

all of the numbers in order. - 34 33 5 5 1
- The Mean in this case is 5

Mode

- Here are the ages again
- Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1
- What is the Mode?
- Remember Mode is the MOST FREQUENT
- Try it on your paper and see what you come up

with!

Mode

- Remember, to find the mode, we have to first put

all of the numbers in order. - 34 33 5 5 1
- The Mode in this case is 5

Range

- Here are the ages again
- Dad- 34, Mom- 33, Jack- 5, Alex- 5, Katie- 1
- What is the Range?
- Remember Range is the DIFFERENCE
- Try it on your paper and see what you come up

with!

Range

- Remember, to find the range, we have to first put

all of the numbers in order. - 34 33 5 5 1
- The highest age is 34, and the lowest is 1
- Now we need to subtract to find the difference
- 34-1 33
- The range is 33

Next, Try it at home with your Family!

To practice more, or to go for more help, then

try some of these websites!

- http//www.bbc.co.uk/schools/revisewise/maths/data

/12_act.shtml - http//www.mathgoodies.com/lessons/toc_vol8.shtm
- http//math.about.com/library/weekly/aa020502a.htm