Total number of selections = 64C2 = 64 x 63/2 = 2016
In each row, there will be seven pairs of squares that share a common side.
Thus, a total of 7x8 = 56 pairs in all the rows.
Similarly, in each column, there will be seven pairs of squares that share a common side. Thus, a total of 7x8 = 56 pairs in all the columns.
Thus, the required probability = 56 + 56/2016 = 112/2016.
Hence, option A is the correct answer.
A | B | C | D | Average |
---|---|---|---|---|
3 | 4 | 4 | ? | 4 |
3 | ? | 5 | ? | 4 |
? | 3 | 3 | ? | 4 |
? | ? | ? | ? | 4.25 |
4 | 4 | 4 | 4.25 |