Find the mean height of the students given in table.
Height in centimeters
Number of students
(Frequency)
101 – 110
111 – 120
121 – 130
131 – 140
141 – 150
151 – 160
8
15
24
40
10
3
Total
100
It appears that the mean value will lie the class 131140. The mid value (for class mark) of this interval is 135.5. Take a = 135.5, the width of each interval is c = 10.
Height (cm)
Midclass (x_i)
Frequency (f)
x_i f_i
u=(x135.5)/10
u f
101110
105.5
844
3
24
111120
115.5
1732.5
2
30
121130
125.5
3012
1
131140
135.5
5420
0
141150
145.5
1455
1
151160
155.5
466.5
2
6
N =100
∑〖x_i f_i=12930〗

∑〖u f= 62〗
total answers (1)
start bookmarking useful questions and collections and save it into your own studylists, login now to start creating your own collections.
It appears that the mean value will lie the class 131140.
The mid value (for class mark) of this interval is 135.5.
Take a = 135.5, the width of each interval is c = 10.
Height (cm)
Midclass (x_i)
Frequency (f)
x_i f_i
u=(x135.5)/10
u f
101110
105.5
8
844
3
24
111120
115.5
15
1732.5
2
30
121130
125.5
24
3012
1
24
131140
135.5
40
5420
0
0
141150
145.5
10
1455
1
10
151160
155.5
3
466.5
2
6
Total
N =100
∑〖x_i f_i=12930〗

∑〖u f= 62〗