Best hard riddles


A man builds a house rectangular in shape. All sides have southern exposure. A big bear walks by, what color is the bear? Why?
White. The house is at the North Pole, so the polar bear.
77.37 %
53 votes

What has everything inside it? Everything you can imagine...even God, the wind, the world, the sky, heaven, earth and everything that comes to your mind.
The alphabet.
77.23 %
69 votes

Using only and all the numbers 3, 3, 7, 7, along with the arithmetic operations +,-,*, and /, can you come up with a calculation that gives the number 24? No decimal points allowed. [For example, to get the number 14, we could do 3 * (7 - (7 / 3))]
7 * ((3 / 7) + 3) = 24
77.20 %
47 votes

Why are manhole covers round? Do manhole covers really need to be circular?
Manhole covers are round so that they won't fall through the hole into the sewer below them. No matter how you turn the cover, you won't be able to push the cover through the hole. However, if you were to have square manhole covers, you would be able to rotate the cover such that one of the edges of the square cover is lined up with the diagonal line of the square hole, which would allow the cover to fall through, causing countless problems that the general public would rather avoid.
77.20 %
47 votes