[405.—CARD MAGIC SQUARES.—solution]
Arrange the cards as follows for the three new squares:—
| 3 | 2 | 4 |
| 4 | 3 | 2 |
| 2 | 4 | 3 |
| 6 | 5 | 7 |
| 7 | 6 | 5 |
| 5 | 7 | 6 |
| 9 | 8 | 10 |
| 10 | 9 | 8 |
| 8 | 10 | 9 |
Three aces and one ten are not used. The summations of the four squares are thus: 9, 15, 18, and 27—all different, as required.
[406.—THE EIGHTEEN DOMINOES.—solution]
