It's a classic dilemma because it pits utilitarianism against individual rights.

The greatest good for the greatest number (utilitarianism) would make the five survive. But the single "fat man" has a right not to be killed.

We don't know any details about the individuals involved. What if the single "fat man" is someone who has been spending his life helping others. What if he is a brilliant doctor on the brink of curing cancer? And what if the five are life-long gang members on their way to commit mass murder ?

Nope but it's how you debate your answer that will differentiate you from a psychopath. So when somebody ask you these mind trap questions just pretend it's a hard dilemma to answer (show strained emotional thinking) and nobody will appear, tackle you and put you in a straight jacket. I hate when that happens. ugh!