The 160 pupils at a certain village school are all registered with the school dentist.
Of the 75 girls, only 25 of them have seen the dentist in the past year, the others have not.
However, 34 of the boys have seen the dentist, and the rest have not.
Each child's records are kept on a separate record card.
A record card is selected at random.
Let A represent the event that the child on the card has seen the dentist in the past year.
Let B represent that the child referred to is a boy.
(a) Find P(A intersect B)
We have the following facts:
(b) Find P(A' intersect B')