M M M R…
Mean
Median
Mode
Range
Let’s talk about the rules…
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Every time you see RED font, write your
answer on your dry erase board (or note
card)
DO NOT hold up your answers until I ask you
to
Question #1
What was the name of this lesson?
Mean, Median, Mode, & Range
(MMMR)
The “Golden Rule” of MMMR
When you get a set of data, the FIRST thing
you should do is…
ARRANGE THE DATA IN NUMERICAL
ORDER FROM SMALLEST TO LARGEST!
Ready to show me how smart you are?
Problem #2
Apply the “Golden Rule” of MMMR to the
following: 3, 5, 6, 7, 2, 8, 4, 6
Brilliant!
2, 3, 4, 5, 6, 6, 7, 8
Alright, now that we have that out of the way…
Let’s talk about MEAN
I’m not mean! Are you?
The MEAN = the average of a set of numbers
Sound familiar?
Steps to find the MEAN
(Ex.) 6, 3, 6, 4, 4, 3, 7, 7
Apply the “Golden Rule” (just in case…)
3, 3, 4, 4, 6, 6, 7, 7
2. Add the numbers in the set
3 + 3 + 4 + 4 + 6 + 6 + 7 + 7 = 40
3. Divide by the total number in the set
40/8 = 5, so the MEAN is 5!
1.
Who was paying attention?
Problem #3
What is a synonym for MEAN?
Problem #4
True or false?
The Mean of the set DOES NOT have to be
one of the numbers in the set.
#3 Another name for MEAN is AVERAGE
#4 TRUE: “The mean of the set does not have
to be one of the numbers in the set”
Remember the example we just did?
The set was: 3, 3, 4, 4, 6, 6, 7, 7
The mean was 5.
*Notice that 5 IS NOT one of the numbers in
the original set!
Stuck in the middle…
Is the MEDIAN!
The MEDIAN is the middle
number of a set of data.
(Ex.) 3, 5, 2, 7, 5, 1, 8
Step #1 Apply the “Golden Rule”
1, 2, 3, 5, 5, 6, 7, 7, 8
Step #2 Count to find the middle number
1, 2, 3, 5, 5, 6, 7, 7, 8
So…5 is the MEDIAN
*Notice that there are EXACTLY 4 numbers to
the right and 4 numbers to the left
(Ex.) 2, 3, 5, 1, 10, 8, 9
Step #1: Golden Rule
1, 2, 3, 5, 6, 8, 9, 10
Step #2: Find middle number
1, 2, 3, 5, 6, 8, 9, 10
Oh, no! There are TWO middle numbers!
Step #3: Find the AVERAGE of the middle
numbers: (5 + 6)/2
MEDIAN = 5 1/2
Basically….
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If the data set is an odd number, the middle
number is the MEDIAN
(Ex.) 1, 2, 3, 4, 5
3 is the MEDIAN
If the data set is an even number, there are
two middle numbers, so the MEDIAN is…
An average of the two middle numbers!
(Ex.) 1, 2, 3, 4
2+3=5
5/2 = 2 ½ is the MEDIAN
M…M….MODE!
The MODE is the number in a set of data that
occurs MOST often
MODE = MOST often
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A data set can have ONE mode
(Ex.) 1, 2, 2, 3
Mode = 2
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A data set can have MORE THAN ONE mode
(Ex.) 1, 1, 2, 2, 3 Mode = 1 and 2
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A data set can have NO mode
(Ex.) 7, 3, 2,
Mode = none
FIND THE MODE:
A) 6, 10, 22, 14, 15, 10, 13, 6, 17, 14
B) 5, 7, 3, 6, 8, 0, 1, 2, 11, 19, 4, 9, 12
C) 7, 3, 4, 8, 6, 4, 9, 2
A) Mode = 6, 10, 14
B) Mode = none
C) Mode = 4
Give me an R! A! N! G! E!
What’s that spell? RANGE!
Range is the difference between the largest
number in the set and the smallest number in
the set.
(Ex.) 4, 5, 10, 2
Golden Rule: 2, 4, 5, 10
Subtract the smallest from the largest: 10 – 2
So, the RANGE is 8!
One last problem…
Find the range for the following set of data:
3, 5, 7, 2, 9, 2, 8,
9 was the biggest number, and 2 was the
smallest….
SO
The answer is 9 – 2 =
7!