CAT 2002 — QA Question 35
Permutation & CombinationEasy
In how many ways, we can choose a black and a white square on a chess board such that the two are not in the same row or column?
Answer & solution
Correct answer: None of these
- A
32
- B
96
- C
24
None of these
Solution
The number of ways of selecting 1 black square is 32.
âµ 8 white squares in the corresponding row and column cannot be selected.
∴ The number of ways of selecting the white square is 24.
∴ Total number of required ways = 32 × 24 = 768
Hence, option (d).