1. Mean, Median, Mode and
Range
The Basics of Statistics

2. Did You Know…
That you
probably use
Statistics such
as Mean,
Median, Mode
and Range
almost every
day without
even realizing

3. 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!

4. 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!

5. Mean Example
Here is an example test scores for Ms.
Math’s class.
82 93 86 97 82
To find the Mean, first you must add up all of
the numbers.
82+93+86+97+82= 433
Now, since there are 5 test scores, we will
next divide the sum by 5.
440÷5= 88
The Mean is 88!

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

7. Median Example
 First, let’s 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!

8. Median Example #2
Now, let’s 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.
86+88= 174 174÷2= 87
Here the Median is 87

9. Mode
 The Mode refers to the number that
occurs the most frequently.
 It’s easy to remember… the first two
numbers are the same! MOde and MOst
Frequently!

10. 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

11. 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!

12. Range Example
 Let’s 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

14. Now YOU try it!!!
This is the Stat Family!
Dad Mom Jack Alex
Katie
34 33 5 5 1

15. 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

16. Mean
Remember, to find the mean, we have to first add
up all of the numbers.
34+33+5+5+1= 80
Then, since there are 6 people in the family, we
next divide by 6.
78÷6= 13
The Mean in this case is 13

17. 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!

18. 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

19. 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!

20. 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

21. 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

22. 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

24. Next, Try it at home with
your Family!

25. To practice more, or to go for
more help, then try some of
these websites!
http://www.bbc.co.uk/schools/revisewise/maths/
http://www.mathgoodies.com/lessons/toc_vol8.s
http://math.about.com/library/weekly/aa020502a