超級聰明豆（六）

Can You Explain?

To answer these questions， you have to let your brain think in different ways. Here’s an example:

Question：A girl who was just learning to drive went down a one-way street in the wrong direction， but didn’t break the law. How come?

Answer：She was walking.

See if you can let your brain switch directions to answer these questions:

1. How can you throw a ball as hard as you can and have it come back to you， even if it doesn’t hit anything， there is nothing attached to it， and no one else catches or throws it?

2. Two students are sitting on opposite sides of the same desk. There is nothing in between them but the desk. Why can’t they see each other?

3. There are only two T’s in Timothy Tuttle. True or 1?

Answer：

1. Throw the ball straight up in the air.

2. The two students have their backs to each other.

3. True. There are only two T’s（upper case）. There are also three t’s（lower case）.

Two Legs， Four Legs

Question：

A puzzle maker looks out a window into his back yard. He sees a mix of boys and cats. He counts 22 heads and 68 legs. He wants YOU to figure out how many boys are there in the yard.

Answer：

The boys plus the cats have a total of 22 heads. Or B + C = 22. Subtracting C from each side of the preceding results in a value for B of 22 - C.

The boys’ legs equal two times the number of boys， the cats’ legs equal four times the number of cats， and the total number of legs equals 68. Or 2B + 4C = 68. Using the value for B already calculated， the last equation can be rewritten as 2 (22 - C) + 4C = 68， or 44 - 2C + 4C = 68， which， by addition and subtraction， becomes 2C = 24， or C = 12.

There are 12 cats and 10 boys in the back yard.

編輯/孫櫟櫟