On an n times n chessboard,the total number o | vedclass

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(C) The total number of rectangles (including squares) on an $n 	imes n$ grid is given by $\left(\frac{n(n+1)}{2}ight)^2$. The total number of squa

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$18$

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(C) The total number of rectangles (including squares) on an $n 	imes n$ grid is given by $\left(\frac{n(n+1)}{2}ight)^2$. The total number of squares on an $n 	imes n$ grid is given by $\frac{n(n+1)(2n+1)}{6}$. The number of rectangles that are not squares is $\left(\frac{n(n+1)}{2}ight)^2 - \frac{n(n+1)(2n+1)}{6} = 350$. For $n=6$: $\left(\frac{6 	imes 7}{2}ight)^2 - \frac{6 	imes 7 	imes 13}{6} = 21^2 - 91 = 441 - 91 = 350$. Thus,$n=6$. The total number of squares is $n^2 = 6^2 = 36$. Since the board has an equal number of black and white squares,the number of white squares is $\frac{36}{2} = 18$.

On an $n \times n$ chessboard,the total number of rectangles which are not squares is $350$. Then,the number of white squares on the chessboard is .......

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