Arrange the cards as follows for the three new squares:--
3 2 4 6 5 7 9 8 10 4 3 2 7 6 5 10 9 8 2 4 3 5 7 6 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.
405.--CARD MAGIC SQUARES.
From Amusements in Mathematics by Henry Ernest Dudeney.
