Note: If the divided result is fraction, it must be round up. If it is divisibly devided, the result must always be plus 1. 3.The Class Interval must be written in order from Min-Max, or Max-Min 4. Finding the Frequency of each Class Interval by using mark Example2: Draw a Frequency Distribution Table by setting the Class Interval width to 5 with belows data. The data is the height of 36 Vocational Diploma students. xxxxxxxxxxxxxxxxx

xxxxxxxxxxxxxx

Direction:

1. Range = Max score - Min score

= 180-152

= 28

2. Set Width or I =5

Number of Intervals = Range

I

Draw a Frequency Distribution Table

Class IntervalMarkFrequency (f)

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Example3: From Example2, Draw a 10 levels Frequency Distribution Table Direction:

1. Range = Max score -Min score

2.Set the Class Interval to 10 levels

Draw a Frequency Distribution Table

Class IntervalMarkFrequency(f)

Frequency Table has technical terms as follows:

1. Lower Limit ขีดจำกันล่าง is the minimum value of each Class Interval. For example, 21-30, 31-40, 41-50 The min value is 21,31,41 2.Upper Limit ขีดจำกัดบน is the maximum value of each Class Interval. For example, 21-30, 31-40, 41-50 The max value is 30,40,50

3.Lower Boundary ขอบล่าง is the mid-value between Lower Limit and next to Upper Limit of the below Class Interval. Lower Boundary = the Lower Limit of Class Interval +the Upper Limit of the below Class Interval

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For example: the minimum value of Class Interval 21 -30 = 21+20/2 =20.5 4. Upper Boundary ขอบบน is the mid-value between Lower Limit and next to Upper Limit of the below Class Interval. Lower Boundary = Upper Limit of the Class Interval + Lower Limit of the lower Class Interval For example: Upper Boundary 0f Interval Class 21-30 = 30+31/2=30.5 5.Mid point จุดกึงกลาง is the middle of Class Interval range Mid Point = Lower Boundary +Upper Boundary/2

or Mid Point = the Lower Limit of Class Interval +the Upper Limit /2 For example. The Mid Point of Class Interval of 21-30 is 20.5+30.5/2=25 or The Mid Point of Class Interval of 21-30 = 21+30/2=25.5

Example4: , Find the values, Upper Limit, Lower Limit, Lower Boundary, Upper Boundary and Mid Point from the below table. Class Interval/Frequency/ Lower Limit/ Upper Limit/ Lower Boundary/ Upper Boundary/ Mid Point/ PAGE22

Class Interval/Frequency/ Lower Limit/ Upper Limit/ Lower Boundary/ Upper Boundary/ Mid Point/ Relative Frequency ความถี่สัมพัทธิ์: , is ratio of frequency in that Class Interval with the sum of all frequencies. Relative Frequency = Frequency of that Class Interval/ The sum of all frequencies Relative Frequency Percantage = Frequency of that Class Interval/ The sum of all frequencies x 100 Example 5: Table shows Direction of finding Relatiove FRequency and Relative Frequency Percentage

Class Interval/ Frequency/ Relative Frequency/ Relative Frequency Percentage PAGE23

Cumulative Frequency ความถี่สะสม Distribution Cumulative Frequency is the sum of Class Interval Frequency and the class that has lowest value Relative Cumulative Frequency

Relative Cumulative Frequency = Cumulative Frequency of that Class Interval/ the sum of Class Interval Frequency Relative Cumulative Frequency Percentage = Cumulative Frequency of that Class Interval/ the sum of Class Interval Frequency x 100 Example6: Table shows Relative Cumulative Frequency and Relative Cumulative Frequency Percentage PAGE24

Exercise 1.2

1. The belows data shows The Vocational Diploma students weight of 25 persons xx xxxxxxxxx

Draw a Frequency Distribution table by arrange values order and answer Weight Kg.MarkFrequency

1.1 The student who has the maximum weight is .... person(s) 1.2 The weight of most students are ..... Kg.

1.3 The number of students who has weight higher than 60 are ..... persons 2.Belows data shows the Vocational Diploma students height as xxx xxxxxxxxx

Draw a Frequency Distribution table by width of 6

2.1 The student who...