Mental Nuts-- Can You Crack 'em?

[ZenGum]

Originally Posted by footfootfoot

Bonus Nut:

If it takes 4 men 3 days to dig 2 holes, how long does it take one man to dig half a hole?

Since it takes six man-days to dig a hole, it should take one man three days to dig half a hole, but you might object that you can't dig "half a hole", because that would still be a hole. However, a man can dig half a hole, it all depends on someone else digging the other half of the hole. And since you stipulated one man, he'll have to come back and do the other half himself. So it turns out it takes six days after all. First three days for the half he is digging, and then another three days to make the first half, well, a half.