89 Assume that a researcher randomly selects 6 newborn babie

#8-9: Assume that a researcher randomly selects 6 newborn babies and counts the number of girls selected, X. The probabilities corresponding to the 7 possible values of X are summarized in the given table. Answer the question using the table. X (# of girls) Pr (X) 0 0.015625 1 0.09375 2 0.234375 3 0.3125 4 0.234375 5 0.09375 6 0.015625 8) Find the probability of selecting 4 or more girls. 9) Find the probability of selecting less than 4 girls. How does this number relate to the answer in the previous question?

Solution

Probability table is as above:

8)P(X>=4) =P(x=4 or t or 6)

= 0.34375

9) P(X<4) = 1-P(X>=4)

= 0.65625

The two total to 1 or the events are complementary