A SHEEP PEN
Arrange eight matches as shown in [Fig. 24], and state that this enclosure, formed by eight hurdles, is supposed to hold one hundred sheep. Ask your friends how many 67 more hurdles would be required to enable the enclosure to contain two hundred sheep? The reply is generally eight more, and your friends will be surprised to learn that only two more hurdles are required—one at each end across the enclosure. Three hurdles being moved to admit of the introduction of the additional two, the pen will, of course, be doubled in size.
Fig. 24.