MATHEMATICAL PUZZLES.

No. I.

Two countrymen were going along the road, each driving sheep.

Said one, "Hi, neighbor, give me one of your sheep, and then I shall

have twice as many as you will have."

"Nay, neighbor," replied the other, "give me one of your sheep, and then

we shall both have the same number."

How many sheep did each have?

No. II.

An old man lived in a little hut by a bridge which crossed a deep river.

One day a wicked water-spirit appeared to him and said: "My friend, I

know you are very poor. Now I will increase whatever money you may have

twofold, asking only in return this small favor, that every time you

cross the bridge you will throw twenty-four cents into the water, and at

the same time the money you have left shall be doubled." The poor old

man was delighted at what he thought a generous offer of the

water-spirit, and faithfully fulfilled all the conditions; but, to his

sorrow and astonishment, when he had three times thrown the tribute of

twenty-four cents to the water-spirit, he found himself penniless.

How much money did he have when the water-spirit first appeared to him?

No. III.

A good mother went to buy eggs for her children, for the Easter season

was approaching, and the eggs were to be colored red and blue. She

bought from a grocer half of his entire stock and half an egg more. Then

a second woman came, and she bought half of what the grocer had

remaining and half an egg more. A third woman and a fourth woman did the

same thing, and in the end the grocer had one egg left.

How many had he in the beginning?

No. IV.

A man had seven sons, and a property of $49,000. Now the younger sons

were jealous because their father spent more for the elder brother than

he did for them, and they entreated him to make his will in their favor.

To satisfy their demands he made his will, and the younger sons were

contented. This is the will: The oldest son to have $1000 and an eighth

of what remained; the second son to have $2000 and an eighth of what

remained; the third, $3000 and an eighth of what remained; the fourth,

$4000 and an eighth of what remained; the fifth, $5000 and an eighth of

what remained; the sixth, $6000 and an eighth of what remained; the

seventh and youngest to have all that remained when the sixth had taken

his share.

What share of the $49,000 did each receive?

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Harper's Young People, November 11, 1879 An Illustrated Weekly · 第 15 / 18 题