An old auto is to drive a stretch of 2 miles, up and down a hill. Because the auto is so old, you cannot drive the first mile (the ascent) faster than 15 miles per hour.
How fast do you have to drive the second mile (going down the hill) in order to get an average speed of 30 miles per hour? Riddle Answer
Below are six discs stacked on a peg. The object is to reassemble the discs, one by one, in the same order on another peg, using the smallest number of moves. No larger disc can be placed on a smaller disc. How many moves will it take?
Here is a light switch. Note the order of the positions. If the light is now at medium and it is switched 3922 times what will be the position of the switch?
A building is being prepared for opening. People are decorating the building with 12 flags. At first they arrange the flags 4 to a side, as shown, but then they see that the flags can be arranged 5 to a side using only 12 flags. How?
In a long, narrow chute there are 8 balls: 4 black ones on the left, and 4 white ones-slightly larger-on the right. In the middle of the chute there is a small niche that can hold 1 ball of either color. The chute’s right end has an opening large enough for a black but not a white ball.
Roll all the black balls out of the chute. You can’t pick them up from the chute. Riddle Answer