Amusements in Mathematics - The Original Classic Edition. Dudeney Henry

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the big flaming placards were exhibited at the little provincial railway station, announcing that the Great ---- Company would run cheap excursion trains to London for the Christmas holidays, the inhabitants of Mudley-cum-Turmits were in quite a flutter of excitement. Half an hour before the train came in the little booking office was crowded with country passengers, all bent on visiting their friends in the great Metropolis. The booking clerk was unaccustomed to dealing with crowds of such a dimension, and he told me afterwards, while wiping his manly brow, that what caused him so much trouble was the fact that these rustics paid their fares in such a lot of small money.

       He said that he had enough farthings to supply a West End draper with change for a week, and a sufficient number of threepenny pieces for the congregations of three parish churches. "That excursion fare," said he, "is nineteen shillings and ninepence, and I should like to know in just how many different ways it is possible for such an amount to be paid in the current coin of this realm."

       Here, then, is a puzzle: In how many different ways may nineteen shillings and ninepence be paid in our current coin? Remember that the fourpenny-piece is not now current.

       33.--A PUZZLE IN REVERSALS.

       Most people know that if you take any sum of money in pounds, shillings, and pence, in which the number of pounds (less than

       PS12) exceeds that of the pence, reverse it (calling the pounds pence and the pence pounds), find the difference, then reverse and add this difference, the result is always PS12, 18s. 11d. But if we omit the condition, "less than PS12," and allow nought to represent shillings or pence--(1) What is the lowest amount to which the rule will not apply? (2) What is the highest amount to which it will apply? Of course, when reversing such a sum as PS14, 15s. 3d. it may be written PS3, 16s. 2d., which is the same as PS3, 15s. 14d.

       34.--THE GROCER AND DRAPER.

       A country "grocer and draper" had two rival assistants, who prided themselves on their rapidity in serving customers. The young

       man on the grocery side could weigh up two one-pound parcels of sugar per minute, while the drapery assistant could cut three one-yard lengths of cloth in the same time. Their employer, one slack day, set them a race, giving Pg 6the grocer a barrel of sugar and telling him to weigh up forty-eight one-pound parcels of sugar While the draper divided a roll of forty-eight yards of cloth into yard pieces. The two men were interrupted together by customers for nine minutes, but the draper was disturbed seventeen times as long as the grocer. What was the result of the race?

       35.--JUDKINS'S CATTLE.

       Hiram B. Judkins, a cattle-dealer of Texas, had five droves of animals, consisting of oxen, pigs, and sheep, with the same number of animals in each drove. One morning he sold all that he had to eight dealers. Each dealer bought the same number of animals, paying seventeen dollars for each ox, four dollars for each pig, and two dollars for each sheep; and Hiram received in all three hundred and one dollars. What is the greatest number of animals he could have had? And how many would there be of each kind?

       36.--BUYING APPLES.

       As the purchase of apples in small quantities has always presented considerable difficulties, I think it well to offer a few remarks on

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       this subject. We all know the story of the smart boy who, on being told by the old woman that she was selling her apples at four for

       threepence, said: "Let me see! Four for threepence; that's three for twopence, two for a penny, one for nothing--I'll take one!"

       There are similar cases of perplexity. For example, a boy once picked up a penny apple from a stall, but when he learnt that the woman's pears were the same price he exchanged it, and was about to walk off. "Stop!" said the woman. "You haven't paid me for

       the pear!" "No," said the boy, "of course not. I gave you the apple for it." "But you didn't pay for the apple!" "Bless the woman! You don't expect me to pay for the apple and the pear too!" And before the poor creature could get out of the tangle the boy had disappeared.

       Then, again, we have the case of the man who gave a boy sixpence and promised to repeat the gift as soon as the youngster had made it into ninepence. Five minutes later the boy returned. "I have made it into ninepence," he said, at the same time handing his benefactor threepence. "How do you make that out?" he was asked. "I bought threepennyworth of apples." "But that does not make it into ninepence!" "I should rather think it did," was the boy's reply. "The apple woman has threepence, hasn't she? Very well, I have threepennyworth of apples, and I have just given you the other threepence. What's that but ninepence?"

       I cite these cases just to show that the small boy really stands in need of a little instruction in the art of buying apples. So I will give a simple poser dealing with this branch of commerce.

       An old woman had apples of three sizes for sale--one a penny, two a penny, and three a penny. Of course two of the second size and three of the third size were respectively equal to one apple of the largest size. Now, a gentleman who had an equal number of boys and girls gave his children sevenpence to be spent amongst them all on these apples. The puzzle is to give each child an equal distribution of apples. How was the sevenpence spent, and how many children were there?

       37.--BUYING CHESTNUTS.

       Though the following little puzzle deals with the purchase of chestnuts, it is not itself of the "chestnut" type. It is quite new. At first

       sight it has certainly the appearance of being of the "nonsense puzzle" character, but it is all right when properly considered.

       A man went to a shop to buy chestnuts. He said he wanted a pennyworth, and was given five chestnuts. "It is not enough; I ought to have a sixth," he remarked! "But if I give you one chestnut more." the shopman replied, "you will have five too many." Now, strange to say, they were both right. How many chestnuts should the buyer receive for half a crown?

       38.--THE BICYCLE THIEF.

       Here is a little tangle that is perpetually cropping up in various guises. A cyclist bought a bicycle for PS15 and gave in payment a cheque for PS25. The seller went to a neighbouring shopkeeper and got him to change the cheque for him, and the cyclist, having received his PS10 change, mounted the machine and disappeared. The cheque proved to be valueless, and the salesman was requested by his neighbour to refund the amount he had received. To do this, he was compelled to borrow the PS25 from a friend, as the cyclist forgot to leave his address, and could not be found. Now, as the bicycle cost the salesman PS11, how much money did he lose altogether?

       39.--THE COSTERMONGER'S PUZZLE.

       "How much did yer pay for them oranges, Bill?"

       "I ain't a-goin' to tell yer, Jim. But I beat the old cove down fourpence a hundred." "What good did that do yer?"

       "Well, it meant five more oranges on every ten shillin's-worth."

       Now, what price did Bill actually pay for the oranges? There is only one rate that will fit in with his statements.

       AGE AND KINSHIP PUZZLES.

       "The days of our years are threescore years and ten."

       --Psalm xc. 10.

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       For centuries it has been a favourite method of propounding arithmetical puzzles to pose them in the form of questions as to the age of an individual. They generally lend themselves to very easy solution by the use of algebra, though often the difficulty lies in stating them Pg 7correctly. They may be made very complex and may demand considerable

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