Question: Number of children. The Census Bureau gives this distribution for the number of a family's own children under the age of 18 in American families in 2006:
Number vof children: 0 1 2 3 4
Proportion: 0.53 0.20 0.18 0.07 0.02
In this table, 4 actually represents 4 or more. But for purposes of this exercise, assume that it means only families with exactly 4 children under the age of 18. This is also the probability distribution for the number of children under 18 in a randomly chosen family. The expected value of this distribution is the average number of children under 18 in a family. What is this expected value?