You’re at a job interview and you are requested to make a simple decision.
The interviewer says, “I have a $1 bill and a $5 bill, which one would you like? Don’t worry, if you make the wrong choice, I’ll give you an extra $5. What is your choice?”
ANSWER: Hopefully this answer doesn't disappoint you, but depending on how you look at it, you either can't lose or you can't win.
This is Presh Talalkar's "You Can't Choose Wrong Paradox."
Choosing the $1 appears to be the best option. First of all, if it is the right choice in the interviewer's mind, great! But if it's the wrong choice, you get $5 more which gives you $6, which is more than the $5 from the other choice, so that would make it the better or "right" choice. The same thing happens if you pick the $5. You can't lose!
BUT... If you think taking the $5 bill is the right choice, then that means taking the $1 bill was the wrong choice which means you don't get the extra $5. So taking $5 nets you less money making it the wrong choice. So you can't win.