wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

The mean of the following frequency distribution is 62.8 and the sum of the observation is 50. Find the missing frequencies F1 and F2.
Class0 - 2020 - 4040 - 6060 - 8080 - 100100 - 120Total
Frequency5F110F27850

Open in App
Solution

Given mean of frequency distribution is 62.8
& the sum of all frequencies is 50
Class mid point of class (xi)
frequency (fi) fixi
020
2040
4060
6080
80100
100120
10
30
50
70
90
110
5
f1
10
f2
7
8
50
30f1
500
70f2
630
880
502060+30f1+70f2
fi=50

30+f1+f2=50f1+f2=5030=20

f1+f2=20 ___(1)

mean ¯x=fixifi=2060+30f1+70f250

62.8×50=2060+30f1+70f2

30f1+70f2=31402060=1080

10(3f1+7f2)=1080

3f1+7f2=108 __(2)

f1=9(1)f2=20f1=209

f2=11

f1=9,f2=11

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Introduction to Statistics
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon