1. A secretary types three letters and the three corresponding envelopes. In a hurry, he places at random one letter in each envelope. What is the probability that at least one letter is in the correct envelope?
2. Consider poker hands drawn from a well-shuffled deck as described in Example 1.3.4. Determine the probability of a full house, i.e, three of one kind and two of another.
Example 1.3.4
