Assesment in learning

1. GOOD DAY
EVERYONE!

2. MEAN
AND
MEAN GROUPED DATA

3. MEAN
The mean is the average or a
calculated central value of a set of
numbers that is used to measure the
central tendency of the data. Central
tendency is the statistical measure
that recognizes the entire set of data
or distribution through a single value.

4. Formula:

5. Examples:
 Find the mean of 10,20,30,40,50.
Mean = 10 + 20 + 30 + 40 + 50 / 5
= 150 / 50
= 30
Find the mean terms of 56, 32, 48, 29, 13, 36, 47.
Mean = 56 + 32 + 48 + 29 + 13 + 36 + 47 / 7
= 261 / 7
= 37.29

6. Let’s try this!
 Find the mean terms of 66, 55, 33, 22, 44, 77, 88.
 Find the mean of the following group of numbers 67, 89,
45, 87, 91, 35,75, 89.
Mean = 66 + 55+ 33 + 22 + 44 + 77 + 88 / 7
= 385 / 7
= 55
Mean = 67 + 89 + 45 + 87 + 91 + 35 + 75 + 89 / 8
= 578 / 8
= 72.3

7. MEAN GROUP DATA
Mean of grouped data is the process of finding
the average of a set of data that are grouped
together in different categories. To determine
the mean of a grouped data, a frequency table
is required to set across the frequencies of the
data which makes it simple to calculate.

8. Formula:
x̄ = Σf•m/Σf
Where:
• x̄ is the mean value of the set of given data
• f is the frequency of each class
• m or x is the mid-interval value of each class

9. Example:
Grade Frequency
(f)
Midpoint or
classmark
(m) or (x)
F•m
40-49 2 44.5 89
50-59 5 54.5 272.5
60-69 7 64.5 381.5
70-79 9 74.5 670.5
80-89 8 84.5 676
90-100 6 95 570
Total: 37 Total: 2,659.5
m= lower + upper / 2
x̄ = Σf•m/Σf
= 2,659.5 / 37
= 71.9

11. Exercise:
Part 1
 Find the mean:
1. 34,56,65,22,11,24,87.
2. 99,127,234,245,88.
3. 45,32,78,45,34,98,31,62.

12. Part II:
 Solve the mean group data.
Age Midpoint
x
Number
f f•x
0 - 9 20
10 - 19 21
20 - 29 23
30 - 39 16
40 - 49 11
50 - 59 10
60 - 69 7
70 - 79 3
80 - 89 1