MEAN DEVIATION OF UNGROUPED DATA GRADE 7 MATHEMATICS QUARTER 4 MEAN DEVIATION IS THE DISTANCE BETWEEN THE MEAN AND THE SCORES

1. Do you
remember
MEAN? 𝑥

2. MEAN
AEVRGAE

3. MEAN
AVERAGE

4. How to compute
MEAN?
Add all the
scores and
divide it by
the number of
scores
𝑥 =
𝑥
𝑁
Example: 4, 3, 5,
9, 4
𝑥 =
4 + 3 + 5 + 9 + 4
5
𝑥 =
25
5
𝑥 = 5

5. 𝑥 = 4
5, 4, 2, 3, 7, 3
What if you are task to compute
for the mean of the following
scores?
𝑥 = 5
8, 6, 4, 2
𝑥 = 3
1, 3, 5, 1, 4, 4,
3

6. Can You See
a Pattern?
Pre-Activity

7. Mean:
______________
Mean:
______________
Can You See a Pattern?
14, 13, 19,
14, 5
10, 12, 12,
15, 20, 27
13
1, 0,
6, 1, 8
Deviation:
___________
16
6, 4, 4,
1, 4, 9
Deviation:
___________

8. MEAN DEVIATION
Here is where your presentation begins

9. At the end of the lesson, you are expected to:
 Define mean deviation
 Familiarize the steps in solving mean deviation of
ungrouped data
 Compute the mean deviation of ungrouped data
 Identify real-world situations pertaining to mean
deviation
Lesson Objectives:

10. Mean Deviation
Where:
● 𝑀𝐷 – is the mean deviation
● 𝑥 – is the individual score
● 𝑥̅ – is the mean
● 𝑁 – is the number of scores or
cases
● |𝑥−𝑥̅| – is the absolute value of the
deviation from the mean
- the average distance between each data
value and the mean
𝑀𝐷 =
𝑥 − 𝑥
𝑛

11. 1. Find the mean for all cases
2. Find the absolute difference between each
score and the mean
3. Find the sum of the differences and divide it
by the number of scores or cases
STEPS IN COMPUTING THE
MEAN DEVIATION

12. Step 1: Find the mean
for all cases
𝑥 =
𝑥
𝑁
Example 1:
Find the mean deviation
of the following number of
hours spent by students in
social media per day.
No. of hours spent: 6, 4, 3,
6, 8, 10, 12, 6, 10, 5
Scores (x) 𝒙 𝒙 − 𝒙
6
4
3
6
8
10
12
6
10
5
𝑥 − 𝑥
7
7
7
7
7
7
7
7
7
7

13. Step 2: Find the absolute
difference between each
score and the mean
Scores (x) 𝒙 𝒙 − 𝒙
6 7
4 7
3 7
6 7
8 7
10 7
12 7
6 7
10 7
5 7
𝑥 − 𝑥
𝟔 − 𝟕 = −𝟏 = 𝟏
1
3 𝟒 − 𝟕 = −𝟑 = 𝟑
4 𝟑 − 𝟕 = −𝟒 = 𝟒
1 𝟔 − 𝟕 = −𝟏 = 𝟏
1 𝟖 − 𝟕 = 𝟏 = 𝟏
3 𝟏𝟎 − 𝟕 = 𝟑 = 𝟑
𝟏𝟐 − 𝟕 = 𝟓 = 𝟓
5
𝟔 − 𝟕 = −𝟏 = 𝟏
1
𝟏𝟎 − 𝟕 = 𝟑 = 𝟑
3
𝟓 − 𝟕 = −𝟐 = 𝟐
2

14. Step 3: Find the sum of the
differences and divide it by
the number of scores or
cases
𝑴𝑫 =
𝑥 − 𝑥
𝑁
Scores (x) 𝒙 𝒙 − 𝒙
6 7 1
4 7 3
3 7 4
6 7 1
8 7 1
10 7 3
12 7 5
6 7 1
10 7 3
5 7 2
𝑥 − 𝑥 = 24
𝑴𝑫 =
24
10
𝑴𝑫 = 𝟐. 𝟒

15. Step 1: Find the mean for all cases 𝑥 =
𝑥
𝑁
Step 2: Find the absolute difference between each score and the
mean (fill this on the table)
Step 3: Find the sum of the differences and divide it by the
number of scores or cases
𝑴𝑫 =
𝑥 − 𝑥
𝑁
Example 2:
Solve for the mean deviation of the Mathematics test
scores obtained as follows: 40, 30, 20, 10.

16. Step 1: Find the mean for all cases 𝑥 =
𝑥
𝑁
Step 2: Find the absolute difference between each score and the
mean (fill this on the table)
Step 3: Find the sum of the differences and divide it by the
number of scores or cases
𝑴𝑫 =
𝑥 − 𝑥
𝑁
Example 3:
In a survey made by Teacher Geeya, five students of Grade 7 Bravery
revealed the number of hours they spend browsing the internet on
weekends:
3, 5, 6, 4, 7
Find the mean deviation of the data presented.

17. Mean:
______________
Deviation:
___________
Mean:
______________
Deviation:
___________
Can You See a Pattern?
14, 13, 19, 14, 5 10, 12, 12, 15, 20,
27
13
1, 0, 6, 1,
8
Mean
Deviation
Mean
Deviation
16
6, 4, 4, 1, 4,
9

21. SEATWORK
Big numbers catch your
audience’s attention

22. Aevin asked the shoesize of 10 of
his friends and obtained the
following scores:
9, 8, 3, 5 ,5, 6, 4, 5, 8, 7
Compute the mean deviation.

23. Assignment:
A teacher gave a 10-item
test in remedial Mathematics
to eight students and
obtained the following
scores:
3, 4, 4, 5, 5, 5, 7, 7
Compute the mean
deviation.