Question

Find the
mean of the following data using direct method
C.I
15-25
25-35
35-45
45-55
55-65
65-75
75-85
F
6
11
7
4
4
2
1
​

Answer 1

Answer:

39.71

Step-by-step explanation:

C.I 15-2525-3535-4545-5555-6565-7575-85

F 6 11 7 4 4 2 1

X 20 30 40 50 60 70 80

fx 120 330 280 200 240 140 80

£fx= 1390

£f= 35

mean= £fx/£f

= 1390 / 35

=39.7142857

= 39.71 approximately