Option 2 : 41/64

**Concept:-**

1. Probability = Favourable cases/Number of cases

2. There are 32 pieces on chess board, 16 each of white and black.

**Calculation:-**

Total number of squares = 8 × 8 = 64

Number of pieces on the board = 32 - 5 - 4 = 23

Probability of getting empty square = (64 - 23)/64 = 41/64