426.--THE HYMN-BOARD POSER.

The worthy vicar of Chumpley St. Winifred is in great distress. A little

church difficulty has arisen that all the combined intelligence of the

parish seems unable to surmount. What this difficulty is I will state

hereafter, but it may add to the interest of the problem if I first give

a short account of the curious position that has been brought about. It

all has to do with the church hymn-boards, the plates of which have

become so damaged that they have ceased to fulfil the purpose for which

they were devised. A generous parishioner has promised to pay for a new

set of plates at a certain rate of cost; but strange as it may seem, no

agreement can be come to as to what that cost should be. The proposed

maker of the plates has named a price which the donor declares to be

absurd. The good vicar thinks they are both wrong, so he asks the

schoolmaster to work out the little sum. But this individual declares

that he can find no rule bearing on the subject in any of his arithmetic

books. An application having been made to the local medical

practitioner, as a man of more than average intellect at Chumpley, he

has assured the vicar that his practice is so heavy that he has not had

time even to look at it, though his assistant whispers that the doctor

has been sitting up unusually late for several nights past. Widow Wilson

has a smart son, who is reputed to have once won a prize for

puzzle-solving. He asserts that as he cannot find any solution to the

problem it must have something to do with the squaring of the circle,

the duplication of the cube, or the trisection of an angle; at any rate,

he has never before seen a puzzle on the principle, and he gives it up.

[Illustration]

This was the state of affairs when the assistant curate (who, I should

say, had frankly confessed from the first that a profound study of

theology had knocked out of his head all the knowledge of mathematics he

ever possessed) kindly sent me the puzzle.

A church has three hymn-boards, each to indicate the numbers of five

different hymns to be sung at a service. All the boards are in use at

the same service. The hymn-book contains 700 hymns. A new set of numbers

is required, and a kind parishioner offers to present a set painted on

metal plates, but stipulates that only the smallest number of plates

necessary shall be purchased. The cost of each plate is to be 6d., and

for the painting of each plate the charges are to be: For one plate,

1s.; for two plates alike, 11¾d. each; for three plates alike,

11½d. each, and so on, the charge being one farthing less per plate

for each similarly painted plate. Now, what should be the lowest cost?

Readers will note that they are required to use every legitimate and

practical method of economy. The illustration will make clear the nature

of the three hymn-boards and plates. The five hymns are here indicated

by means of twelve plates. These plates slide in separately at the back,

and in the illustration there is room, of course, for three more plates.

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