Question

W LUUN YUGSUN Laine
A) Find the mean of the following data by deviation method.
Class 10-9 10-19 20-29 30-39 40-49 50-59 60-69
Frequency 3 5 7 13 11 7 10
Class
0-9
10-1
​

Answer 1

first add it and divide by the number of observations