Mental Exercise

River Crossing

A traveling animal keeper has a mongoose, snake, hamster, and cheese. She encounters a river with only a small boat available for the crossing. Only two of the items can be carried in the boat with each crossing. Moreover, the mongoose can’t be left alone with the snake, the snake can’t be left with the hamster, and the hamster can’t be left with the cheese. How can she get the animals and cheese across the river?

Cabin in the Woods

A man builds a one room cabin with plans to add rooms as needed. But he has special rules he follows:

 Ø The cabin only has a single floor, all rooms are on the same floor.

 Ø It has only rooms, no hallways.

 Ø Every room must connect directly to every other room with a door.

The man adds rooms to his cabin until he can add no more without breaking his rules. How many rooms does the cabin finally have?

Link Chain

Someone finds four segments of chain links: one segment with two links, one with three links, one with four links, and one with five links. The separate chains are taken to a blacksmith so that they can be made into one continuous loop. The blacksmith says that it takes fifteen minutes to break and reconnect an individual link. The customer says that they will return in an hour to pick up the completed chain loop. The Blacksmith says that it will not take that long. Why?

What Am I?

I am used for both cutting and grinding. When I become damaged, people often remove me or fill me. To animals I am a useful tool. What am I?

Interesting Analogy

Consider the analogy:

     Snorkel is to  SCUBA  as

     Jet         is to  _______

The blank should be replace by which of the following to logically complete the analogy:  Engine or Propeller or Rocket or Explosion ?

Cut the Cloth

A tailor has a piece of cloth. The cloth is folded in half so that the top and bottom completely overlap. The folded cloth is cut it in half. Now there are three pieces, two of which are the same shape as the original piece. What is the shape of the third piece (when unfolded)?

Answer

River Crossing

In five crossing the animals and cheese can be moved across the river.  C=cheese, H=hamster, S=snake and M=mongoose:

Cabin in the Woods

Four rooms.

Link Chain

If the three links of the three-link chain are each broken they can be used to join the other three segments to make one continuous chain loop. This will then only take 45 minutes.

What Am I?

Teeth.

Interesting Analogy

Rocket. A snorkel uses outside air, while SCUBA carries its own air. Similarly, a Jet uses the surrounding air but a Rocket carries its own air.

Cut the Cloth

Start with a triangular piece and fold it on the dotted line as shown in the figure on the left. Then the folded piece is cut on the dotted line shown in the figure on the right.

Of the three resulting pieces, two are the same shape as the original and the other unfolds to a square.