-29 f=40; class 30-39 f=20; class 40-49 f=10.
1) How many classes are there in this frequency distribution?
2) What is the midpoint of the 3rd class?
3) What is the total number of observations in the frequency distribution?
4) What is the relative frequency of the 3rd class?
5) n the formula for the standard deviation in this problem do you use "N' or "n-1"?
6) What is the value of the mean?
7) What is the value of the standard deviation?