1. If a lot of 1000 of items has 100 defectives and if a sample of 20 items is randomly selected from the lot without replacement, what is the probability that the sample will contain at least 1 defective?

1. Suppose that you received 5 random cards from a card dealer. You randomly returned 2 cards back to the dealer without looking. What is the probability that two of the five cards that you received from the dealer were Aces and that you returned both Aces back to him?

1. A In how many ways can 5 girls and 5 boys be arranged in a row
2. without restriction?
3. such that the 2 boys are together?
4. such that the 2 boys are together and 2 girls are together?
5. The 5 boys are all sitting together around a dining table?