Site icon Wizako – GRE Prep Blog

GRE Practice: Chess Board Probability

What is the probability that two squares(smallest dimension) selected randomly from a chess board have only one common corner?

Explanation:

From the diagram you see that considering the top two rows, there are 14 ways of choosing two squares with just one common corner.
Like wise rows (2, 3), (3, 4)…….(7, 8) can be considered.
Therefore, number of ways = 14 x 7 = 98

Total number of ways of choosing two squares from a chess board = 

Probability =

=

Listen to the Latest in GRE Podcasts

Exit mobile version