# Thread: Standard Dev and mean of continous data

1. ## Standard Dev and mean of continous data

Salary/Frequency
20-34/4
35-49/20
50-54/41
55-59/25
60-64/3
65-69/6
70-74/8

How do I find the std dev and mean of the above data?

2. Proceed as usual but take the midpoint of the classes as your data value.