A survey of Chaicago sports fans asked them 3 questions about which they prefer. Each fan must give exactly 1 answer to each question. Given a choice between the Cubs and White SOx, 40% chose cubs. Between the Bulls and Blackhawks, 57% chose bulls. between wildcats and maroons, 73% chose wildcats. 18% chose the cubs, wildcats, and bulls. 5% chose white sox, black hawks, and maroons. Of the people who chose cubs, 55% chose bulls. Of the people who chose cubs and wildcats, 60% chose bulls. Of the people who chose White Sox, what percentage chose both bulls and maroons?

To find the percentage of people who chose both Bulls and Maroons among those who chose White Sox, we need to analyze the given information step by step.

Step 1: Let's assign variables to the different groups to make it easier to refer to them:
- Let C represent those who chose the Cubs.
- Let S represent those who chose the White Sox.
- Let B represent those who chose the Bulls.
- Let H represent those who chose the Blackhawks.
- Let W represent those who chose the Wildcats.
- Let M represent those who chose the Maroons.

Step 2: We are given the following information:
- 40% chose the Cubs (C = 40%).
- 57% chose the Bulls (B = 57%).
- 73% chose the Wildcats (W = 73%).
- 18% chose the Cubs, Wildcats, and Bulls (C ∩ W ∩ B = 18%).
- 5% chose the White Sox, Blackhawks, and Maroons (S ∩ H ∩ M = 5%).
- 55% of those who chose the Cubs also chose the Bulls (B | C = 55%).
- 60% of those who chose the Cubs and Wildcats also chose the Bulls (B | C ∩ W = 60%).

Step 3: Now we need to find the percentage of people who chose both Bulls and Maroons among those who chose the White Sox (S).

We can use the principle of inclusion-exclusion to calculate this value.

Percentage = S ∩ B ∩ M = S - (S ∩ H ∩ M) - (S ∩ W ∩ M) + (S ∩ H ∩ W ∩ M)

From the given information, we know that:
S ∩ H ∩ M = 5% (percentage of those who chose White Sox, Blackhawks, and Maroons)
S ∩ W ∩ M = 0% (since no information is provided about the intersection of White Sox, Wildcats, and Maroons)
S ∩ H ∩ W ∩ M = 0% (since no information is provided about the intersection of White Sox, Blackhawks, Wildcats, and Maroons)

Therefore, the percentage of people who chose both Bulls and Maroons among those who chose the White Sox can be calculated as follows:

Percentage = S ∩ B ∩ M = S - (S ∩ H ∩ M) - (S ∩ W ∩ M) + (S ∩ H ∩ W ∩ M)
Percentage = S - (5% + 0% + 0%)
Percentage = S - 5%

Thus, the answer is that the percentage of people who chose both Bulls and Maroons among those who chose the White Sox is simply 5%.