The random variableXis the number of girls of four children born to a couple that is equally likely to have either a boy or a girl. Its probability distribution is as follows

x01234P(X =x)0.06250.25000.37500.25000.0625

1. = E(X) =(Round your answer to one decimal place)

2.(X) =(Round your answer to one decimal place)

3. Among all families with four children, what is the average number of boys?

(Round your answer to one decimal place)