Answer:
15/64 = 23.4 %
Step-by-step explanation:
Let's consider the first two selections. Let's call B the case in which she extracts a boy and G the case in whish she extracts a girl.
For each selection, the probabilty of event B (selecting a boy) is
While the probability of event G (selecting a girl) is
We are asked to find the probability that the first two events are B and then G:
In the first two selections, we have 4 possible combinations:
BB, BG, GB, GG
The probability for each combination is given by:
The second one is the probability we are searching for, so the probability that she will select a boy first and then a girl is 15/64, or 23.4%.