## THE FOUR POSTAGE STAMPS.

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Combination and Group Problems)

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| 1 | 2 | 3 | 4 |

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| 5 | 6 | 7 | 8 |

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| 9 | 10 | 11 | 12 |

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"It is as easy as counting," is an expression one sometimes hears. But

mere counting may be puzzling at times. Take the following simple

example. Suppose you have just bought twelve postage stamps, in this

form--three by four--and a friend asks you to oblige him with four

stamps, all joined together--no stamp hanging on by a mere corner. In

how many different ways is it possible for you to tear off those four

stamps? You see, you can give him 1, 2, 3, 4, or 2, 3, 6, 7, or 1, 2, 3,

6, or 1, 2, 3, 7, or 2, 3, 4, 8, and so on. Can you count the number of

different ways in which those four stamps might be delivered? There are

not many more than fifty ways, so it is not a big count. Can you get the

exact number?

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THE CROSS TARGET.