Question: BINGO involves drawing labeled ping pong balls at random without replacement from a hopper. There are 75 balls with 15 for each of the letters B, I, N, G and O. What is the probability of drawing

a. Two G balls in the first two selections?

b. Three B balls in the first three selections?

c. An I ball followed by a N ball followed by an O ball in the first three selections?

d. An I, N and O ball in any order in the first three selection? NOTE: 18c and 18d are asking different questions; thus, they yield different answers.