Suppose that the genders of the three children of a certain family are soon to be revealed. Outcomes are thus triples of "girls" (g) and "boys" (b), which we write

gbg, bbb, etc. For each outcome, let R be the random variable counting the number of girls in each outcome. For example, if the outcome is bgb, then R(bgb) = 1. suppose that the random variable X is defined in terms of R as follows: X= R-R´-1. The values of X are thus: Calculate the probability distribution function of X, i.e. the function px (x). First, fill in the first row with the values of X. Then fill in the appropriate probabilities in the second row.