Recreational Mathematics Magazine, 1961. |
Páginas
quarta-feira, 7 de março de 2018
Um quadrado mágico de cartas
8 comentários:
Regras para postar comentários:
I. Os comentários devem se ater ao assunto do post, preferencialmente. Pense duas vezes antes de publicar um comentário fora do contexto.
II. Os comentários devem ser relevantes, isto é, devem acrescentar informação útil ao post ou ao debate em questão.
III. Os comentários devem ser sempre respeitosos. É terminantemente proibido debochar, ofender, insultar e/ou caluniar quaisquer pessoas e instituições.
IV. Os nomes dos clubes devem ser escritos sempre da maneira correta. Não serão tolerados apelidos pejorativos para as instituições, sejam quais forem.
V. Não é permitido pedir ou publicar números de telefone/Whatsapp, e-mails, redes sociais, etc.
VI. Respeitem a nossa bela Língua Portuguesa, e evitem escrever em CAIXA ALTA.
Os comentários que não respeitem as regras acima poderão ser excluídos ou não, a critério dos moderadores do blog.
In English:
ResponderExcluirA magic square of cards
The above figure shows a magic square of cards: each row, each column and each main diagonal contains an ace, a king, a queen, and a jack, and all four suits. The central 2 x 2 square and the 2 x 2 squares in the corners also possess the same property. If we observe the four cards in the corners, we also see all four ranks and all four suits. There is no other symmetrical subset [in the figure] that contains all four ranks and all four suits.
Incredible, isn't it?
By the way, yes, it is incredible.
ExcluirYour translation was almost perfect.
ExcluirThe only mistake was in "There is no other symmetrical subset [in the figure] that contains all four ranks and all four suits."
In fact, I wrote that "There are still other symmetrical subsets that contain all four ranks and all four suits."
Oops.
ExcluirActually, there are two more subsets that contain all four suits and all four ranks: each of the two sets that consists of cards that are adjacent to two opposite corners. These sets in the figure are:
ResponderExcluirAce of clubs, king of diamonds, queen of spades, jack of hearts
Ace of spades, king of hearts, queen of clubs, jack of diamonds
Yes, Jake. These subsets also contain all four ranks and all four suits. (There are other ones!!!)
Excluir(Thank you for the almost-perfect translation!!)
Two other subsets containing all 4 ranks and all 4 suits are the pairs of cards in the middle of opposite sides of the square.
ExcluirThe corners of each possible 3 x 3 square also have the special property.
ResponderExcluir