The probability that a football player weighs more than 230 pounds is .69, that he is at least 75 inches tall is .55, and that he weighs more than 230 pounds and is at least 75 inches tall is .43. Find the probability that a randomly selected football player weighs more than 230 pounds or is at least 75 inches tall.

In a class of 35 students, 13 are seniors, 9 are juniors, 8 are sophomores, and 5 are freshmen. If one student is selected at random from this class, what is the probability that this student is

• a. A junior
• b. A freshman

A box contains 10 red marbles and 10 green marbles.

• a. Sampling at random from the box five times with replacement, you have drawn a red marble all five times. What is the probability of drawing a red marble the sixth time?
• b. Sampling at random from the box five times without replacement, you have drawn a red marble all five times. Without replacing any of the marbles, what is the probability of drawing a red marble the sixth time?

Two cards are drawn from a well-shuffled ordinary deck of 52 cards. Find the probability that they are both aces if the first card is

• a. Replaced
• b. Not replaced

Five cards are drawn from a pack of well-shuffled cards without replacement. Find the probability that

• a. 4 are aces and 1 is a king
• b. 3 are 10's and 2 are jacks