Question

A survey asked a group of medical doctors how many children they had fathered. The results are summarized by this ungrouped frequency distribution.

Number of Children	0	1	2	3	4	6
Number of Doctors	18	14	24	14	6	3

(a) Calculate the sample mean for the number of children the doctors had fathered. (Give your answer correct to two decimal places.)


(b) Calculate the variance for the number of children the doctors had fathered using the short-cut formula and verify it with your graphing calculator. (Give your answer correct to two decimal places.)


(c) Calculate the standard deviation for the number of children the doctors had fathered. (Give your answer correct to two decimal places.)

Answer 1

(a) The sample mean for the number of children the doctors had fathered = 1.85

(b) The variance for the number of children the doctors had fathered = 2.18

(c) The standard deviation for the number of children the doctors had fathered = 1.48