A mathematician, an engineer, and a statistician are all interviewed for the same job...(my statistics teacher in college told the class this joke)

Each of them are brought into the bosses office individually and asked only one question.

The mathematician comes in and is asked "what is 2 + 2?" To which he answers "obviously it's 4"

The engineer is asked the same question. "Well it's hard to say for sure, I'd have to make a few calculations, draw up some graphs. Let me get back to you in about a week."

Finally, the statistician is brought in.

"What's 2 + 2?"

The statistician then casually closes all the blinds in the room and slyly asks "what do you want it to be?"