a) Let A be the set of all strings of decimal digits of length 5. For example 00312 and 19483 are two strings in A. You pick a string from A at random. What is the probability that the string has no 4 in it? b) Three distinct numbers between 10 and 25 (inclusive) are chosen at random. What is the probability that the numbers are all composite numbers? c) Suppose that you pick a bit string from the set of all bit strings of length ten. What is the probability that the bit string has more Os than 1s? d) Suppose we want to pick two numbers from {1,2,…,100} randomly. What is the probability that the sum of the two picked numbers is divisible by 5.

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