A ping pong ball fell down into a narrow metal pipe embedded in concrete one foot deep. You have a table tennis racket (bat or paddle), a pair of shoe laces and a large unopened water bottle, which does not fit into the pipe. How can you get the ping pong ball out of the pipe undamaged?
Riddle AnswerHard Riddles
12 Marbles Problem
You have twelve marbles that are identical in size, shape, and color. One of the marbles is heavier in weight than the rest. How can you find the heavier marble by using a balance scale only thrice?
Riddle AnswerProbability Other Child Is a Boy
Mr. Smith has two children. If the older child is a boy, what is the probability that the other child is also a boy?
Riddle AnswerThe Length of One Shoelace
The length of one shoelace is 20cm and half a shoelace.
What is the length of 2 such shoelaces?
Riddle AnswerSliding Coins
Three pennies and three nickles are arranged in a row. The pennies are red and nickles are green in color. The goal is to move them so that the coins are again in a row, with all pennies to the right and nickels to the left.
Each move consists of moving a pair of adjacent coins, and sliding those two coins to a new position without rotating the coins. How can you achieve this (shown below) in three moves?
