Find the total number of rectangles on a normal chessboard.
Find the total number of rectangles on a normal chessboard.
\({ }^8 \mathrm{C}_2 \times{ }^8 \mathrm{C}_2\)
\({ }^8 \mathrm{C}_2+{ }^8 \mathrm{C}_2\)
\({ }^9 \mathrm{C}_2 \times{ }^9 \mathrm{C}_2\)
\({ }^9 P_2 \times{ }^9 P_2\)
Solution
Total number of Rectangles in \(n \times n\) chess board \(=n+1_{c_2} \times n+1_{c_2}\)
\(\therefore\) Total Number of Rectangles in \(8 \times 8\) chess Boord \(=9_{c_2} \times 9_{c_2}\)
Hence, option (c) is correct.