Simple Subtraction
If you have fifteen matches and remove six, how can you obtain a remainder of ten?
Fig. 25.—Showing first arrangement of matches.
Arrange the matches as in [Figs. 25] a, b, and c, and ask a friend the above-mentioned question.
When he gives it up, remove the six matches marked A, B, C, D, E, and F, and you will have the result shown in [Fig. 26].
Fig. 26.—Showing result when six matches have been removed.