Question 165109
Obviously the more 3" blocks the better, MAYBE!
Try 8x8 3" square blocks=24^2=576"^2 Then we need 625-576=49 1" sq blocks for a total of 64+49=113 blocks.
Try 7x7 3" sq blocks=21^2=441"^2 Then we need 625-441=184"^2 of 2" sq blocks
184/4=46 blocks. 49+46=95 blocks. Answer.
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Ed