A prof gave 40 students a test of 3 questions. If 10 students didn't answer the first question, 14 didn't answer the second, and 12 didn't answer the third, how many students answered exactly one question? I'm a bit lost here, I know formulas for permutations but I can't see any that apply here...

Question

anonymous · Answer

thats what I was doing....30 answered 1st question, 10 didn't....26 answered 2nd question, 14 didn't....28 answered 3rd question, 12 didn't....but I am not sure where to go from here...I tried venn diagram, but was not successful. Sorry, not much help here

anonymous · Answer

The total i got was 36/40 who actually answered.

anonymous · Answer

I didn't even get that far...

anonymous · Answer

even if you tag someone to come help, they will not see their notifications unless they refresh

anonymous · Answer

But then.. I was thinking only 4 actually answered one question... No idea

anonymous · Answer

I do not know the answer...I am sorry :(

anonymous · Answer

That's okay, I can't get anywhere on it ):

raden · Answer

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