Answer:
Step-by-step explanation:
A family has four children. If the genders of these children are listed in the order they are born, there are sixteen possible outcomes: BBBB, BBBG, BBGB, BGBB, GBBB, BGBG, GBGB, BGGB, GBBG, BBGG, GGBB, BGGG, GBGG, GGBG, GGGB, and GGGG.
Let X represent the number of children that are girls. Then
1. When X=0, there is one possible outcome BBBB. So
2. When X=1, then there are 4 possible outcomes GBBB, BGBB, BBGB, BBBG, so
3. When X=2, then there are 6 possible outcomes BGBG, GBGB, BGGB, GBBG, BBGG, GGBB, so
4. When X=3, then there are 4 possible outcomes GGGB, GGBG, GBGG, BGGG, so
5. When X=4, then there is one possible outcome GGGG, so
Now, the probability distribution table is