Answer:
28.57% probability that the oldest is a girl and the youngest is a boy, given that there is at least one boy and at least one girl.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
These are all the possible outcomes: from youngest to oldest, b is boy and g is girl
b - b - b - g
b - b - g - b
b - b - g - g
b - g - b - b
b - g - b - g
b - g - g - b
b - g - g - g
g - b - b - b
g - b - b - g
g - b - g - b
g - b - g - g
g - g - b - b
g - g - b - g
g - g - g - b
The nuber of total outcomes is 14.
Desired outcomes:
Oldest(last) girl, youngest(first) boy
b - b - b - g
b - b - g - g
b - g - b - g
b - g - g - g
So 4 desired outcomes
Probability:
4/14 = 0.2857
28.57% probability that the oldest is a girl and the youngest is a boy, given that there is at least one boy and at least one girl.
