Solution

(related to Problem: The Cross Target)

Twenty-one different squares may be selected. Of these nine will be of the size shown by the four $A$'s in the diagram, four of the size shown by the $B$'s, four of the size shown by the $C$'s, two of the size shown by the $D$'s, and two of the size indicated by the upper single $A,$ the upper single $E,$ the lower single $C,$ and the $EB.$ It is an interesting fact that you cannot form any one of these twenty-one squares without using at least one of the six circles marked $E.$

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References

Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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