AP EAMCET202018 Sep 2020Evening ShiftMathematicsPermutation and CombinationActual
Find the total number of rectangles on a normal chessboard.
Options
- A( ^8 C ₂ ^8 C ₂ )
- B( ^8 C ₂+ ^8 C ₂ )
- C( ^9 C ₂ ^9 C ₂ )
- D( ^9 P₂ ^9 P₂ )
Correct answer
C. ( ^9 C ₂ ^9 C ₂ )
Step-by-step solution
Total number of Rectangles in (n n ) chess board (=n+1_ c₂ n+1_ c₂ ) ( ) Total Number of Rectangles in (8 8 ) chess Boord (=9_ c₂ 9_ c₂ ) Hence, option (c) is correct.