Question

Find the mean of the following data
Marks
0-10
10-20
20-30
30-40
40-50
30-60
Number of
Students
12
18
27
20
17
6​

Answer 1

Answer:

Let A = 25 be the assumed mean. Then we have:

Mean, x = A + ∑(fi×di)∑fi

= 25+300100

=28

∴ = 28