Two smallest squares are chose at random on a chess board and `p/q` is the probability that they have exactly one corner in common (`p` and `q` are co-prime) then `q-20p=`

Explanation

To solve the problem of finding the probability that two randomly chosen squares on a chessboard have exactly one corner in common, we can follow these steps:

### Step 1: Understand the Chessboard Configuration
A standard chessboard consists of 8 rows and 8 columns, making a total of 64 squares. Each square can be identified by its row and column coordinates.

**Hint:** Visualize the chessboard and label the squares to understand their positions.

### Step 2: Count the Total Ways to Choose Two Squares
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