You’re a bright person. So consider the following question:

Jack is looking at Anne, but Anne is looking at George. Jack is married, but George is not. Is a married person looking at an unmarried person?

A) Yes.

B) No.

C) Cannot be determined.

Once you’ve tackled that one, think about this:

If it takes five machines 5 minutes to make five widgets, how long would it take 100 machines to make 100 widgets?

If you’re like 80% of college students, you’ll get both questions wrong. Why? You’re lazy. Most intelligent people cut corners. They jump to apparent or obvious answers rather than working through all the details to get the right one. New scientist explains all the gory details, but basically patience and thoroughness don’t seem to correlate well with IQ.

For the record, I botched the first one. I got the second one right, but only because I already knew I flunked the first one and intentionally took my time on it.

Most people answer C) for the first question, but the correct answer is A). Jack appears to be the only married person, so you tend to shortcut the question by turning it into, “Is Anne married?” While it’s true that Anne’s status is unknown, we do know that either she is or isn’t married. If she is, then she’s looking at George, who’s unmarried. If she isn’t then Jack is looking at her. Either way, a married person is looking at an unmarried person.

In the second case, most people jump to the answer of 100 minutes. If it’s all 5’s in the first case, it must be all 100’s in the second. But that’s being lazy. If 5 machines take 5 minutes to make 5 widgets, then each machine turns out a widget every 5 minutes. So 100 machines would turn out 100 widgets in 5 minutes.

What I can’t figure out based on the article is if anyone should feel good about getting the answers correct. They are saying smart people tend to get them wrong, but I have to believe that dumb people are going to get them wrong too, just for different reasons. So I guess all I can conclude is that if you did get them right you are strange unusual.