A comb. Other inanimate objects with teeth like a saw, zipper or a gear can “bite” you. Many people can affirm from painful experience in regards to zippers and saws, and the unfortunate factory worker who is missing a finger can attest to gears. It’s a rare event that anyone would be injured by a comb.
There is an abandoned aquarium in an empty house. The aquarium has three large fish and three small fish. But after a week, one large fish and two small fish die.
A couple has two children. At least one of them is a boy. Assuming the probability of having a boy or girl is 50%, what is the probability that both children are boys?
If you answered 1/2, you’re not without comrades, but the generally accepted answer by statisticians (though not without debate) is 1/3. This is because there are four possible combinations: boy-boy, boy-girl, girl-boy and girl-girl. Since we are told one of the children is a boy (but we don’t know if it’s the first or second child), we can rule out the girl-girl combination, leaving three remaining options. Only one out of 3 is boy-boy, so we get a 1/3 chance.
Because Oct 31 represents the octal (base 8) number 31, which, when converted to decimal, is 25. Dec 25 is short for Decimal 25, thus the two are equal.
A clam or oyster. You harvest clams or oysters on the beach or go diving, and the beach is often windy and rainy. Neither bleeds but are known for having, soft, slimy meat, and people often drink the “clam nectar” or “oyster juice”.
A variation of this brain teaser includes laser printers (they were invented by Gary Starkweather) and bulletproof vests (invented by Casimir Zeglen using silk, though modern vests use Kevlar, so it’s halfway right).