Funny how everyone here, myself included, assumed the numbers were integers!

I like the follow up question of "what if they are floats?" to see if the interviewee knows not to use `==` with floats.

220 = 2 * 2 * 5 * 11. There must be 2 * sqrt(5) * sqrt(11) in that list of numbers. It's about 14.8323969742. Easy to test for it.