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Number of ways of selecting three squares on a chessboard so that all the three be on a diagonal line of the board or parallel to it is 

Answer:

Explanation:

Number of ways 

 $=[(^{3}C_{3}+^{4}C_{3}+^{5}C_{3}+^{6}C_{3}+^{7}C_{3})\times2+^{8}C_{3}]\times2$

  =392