Question 470512
If I pick a person at random what is the probability of picking a man? 15/20 = 3/4. A woman? 5/20 = 1/4.

If I pick a person at random what is the probability the person will be male or over 30? P(male U over 30) = P(male) + P(over 30) - P(male AND over 30) = 3/4 + 11/20 - 10/20 = 4/5.

If I pick a person at random what is the probability the person will be female or under 30? P(female U under 30) = P(female) + P(under 30) - P(female AND under 30) = 1/4 + 9/20 - 4/20 = 1/2.

If I pick two people at random what is the probability of picking a man on the first pick and a woman on the second without replacement? (15/20)*(5/19) = 15/76

What would the probability be with replacement? (15/20)*(5/20) = 3/16.