Question 1180673
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The area of the chess board covered by squares is  64*6.25 = 100 cm^2,


hence, the side length of this part of the chess board is 10 cm.


Add 2 cm from each side, and you will get  10 + 2 + 2 = 14 cm for the side length of the whole chess board 
including the border around it.
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