I was on Google+ last night when I came across a brain teaser. It took me about 20 seconds to figure it out. On average, I'm finding others taking about 2 minutes. Others just gave up, getting angry with me for asking the question.
I have a theory for how long it will take you to figure it out. The more empathetic you are, the less time it will take you. Counter to that, if you are more apathetic toward others, it will take you longer.
What is the number of the parking space containing the car?
So, how long did it take you?