A man has 5 pieces of chain that must be joined into a long chain. He can open ring 3 (first operation), link it to ring 4 (second operation), then unfasten ring 6 and link it to ring 7, and so on.
He could complete his task in 8 operations, but he wants to do it in 6. How does he do it? Riddle Answer
You are to make one cut (or draw one line) – of course it needn’t be straight – that will divide the following shape into two identical parts.
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?