600 children attended summer camp, 58% girls, 42% boys (overall). 25% attended dance camp. If dance camp was exclusively attended by girls, how many girls attended dance camp? The choices are a)150, b)95, c)102, d)118, and e)123. The answer is supposed to be A, but I can't get it. I took 25% of 600 and got 123, then took 58% of 123 but it's not an option. Please help! There must be some underlying factor I'm missing...

Kaye B, Riverdale

Thanks for your question, Kaye. This is a classic word-problem trick -- giving too much information. Let's review the facts first:

• 1. 600 children attended summer camp
• 2. 58% of summer camp attendees are girls
• 3. 42% of summer camp attendees are boys
• 4. 25% of summer camp attendees went to dance camp
• 5. All dance camp attendees are girls

The question asks how many dance camp attendees are girls. Well, fact #5 says that all the attendees were girls, so we just need to know how many attendees went to dance camp.

Facts #2 and #3 don't tell us that, so they are just extra information intended to throw us off the answer.

Fact #1 says there were 600 children, and fact #4 says 25% of them went to dance camp. Therefore, 600 x 25% or 150 children went to dance camp, and they are all girls, so the correct answer is A.

Word problems can be tricky. The key to solving them is to first remember that they may have more information than you need. By avoiding the TMI trick (too much info), you'll have a much better shot at finding out the correct answer.