The set S consists of 5 numbers: {1,2,3,4,5}. If all possible subsets including the null set are created and one subset is chosen at random, what is the probability that the subset has 4 as its largest number? Choose the correct choice from the following answers.
A) 1/2  B) 1/4  C) 1/8  D) 1/16  E) 5/32
The set S has 2^5 = 32 subsets.   The number 5 is in half of these subsets.   Of the remaining 16 subsets, 4 is an element in 8 of them.   Thus 4 is the largest number in 8 subsets of S.   The probability that 4 is the largest number is 8/32 = 1/4.   The answer is 1/4.
<result>B</result>
The set S consists of 5 numbers: {1,2,3,4,5}. If all possible subsets including the null set are created and one subset is chosen at random, what is the probability that the subset has 4 as its largest number?