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I’ve got a bunch of friends at San Diego Comic-Con right now, so I figured I’d use that for the theme for this weekend’s challenge. Of course, I made most of these numbers up, but I didn’t completely pull them out of thin air.

58% of the attendees at Comic-Con this year are male. 10% of the attendees are cosplayers. 15% of the cosplayers are dressed as characters from the Marvel universe. 63% of the cosplayers are female, 20% of whom are dressed as Marvel characters. If 130,000 people attend Comic-Con, what percent of male attendees are cosplayers that are not dressed as Marvel characters? (Round your answer to the nearest tenth of a percent.)

Put your non-anonymous responses in the comments! First correct response wins a Math Guide. Full contest rules here.

UPDATE: A bunch of people got this, but Diane got it first. Solution below the cut.

The key to a question like this is just to figure out everything you can. Since each condition is an either/or condiiton (male or female, cosplay or not cosplay, Marvel or not Marvel) each statement gives you twice as much information as it initially appears to give.

Start by figuring out the total number of male attendees. The question says that 58% of the 13,000 attendees were male, so that’s 75,400. Put that number aside now— we won’t need it for a while.  (Of course, to the point above, that also tells us there are 54,600 female attendees. We don’t need that number, but we know it.)

If 10% of the attendees are cosplayers, that means 13,000 folks showed up in costume. We’re given a bunch of information about them.

First, we’re told how many of them are dressed as Marvel characters. That’s 15% of 13,000, or 1,950.

We’re also told how many of the 13,000 cosplayers are female: 63%, or 8,190 of the 13,000. Which also tells us how many of them are male: 4,810.

Of the 8,190 female cosplayers, we know 20% of them, or 1,638 are dressed as Marvel characters.

If 1,638 of the 1,950 Marvel cosplayers are female, that means the other 312 of them must be male.

Remember what we want now. We want the percentage of male attendees that came in cosplay that was NOT Marvel-inspired.

There are 4,810 male cosplayers, and 312 of them are in Marvel getup. That means 4,498 of them are NOT in Marvel costumes.

Now just find the percentage:

4,498/75,400 × 100% = 5.965517…%

Round that to the nearest tenth, and you’ve got 6.0%.