# Let's re-share it!

Two numbers $$x,y$$ with $$x>y$$ are chosen at random from the set$$\left\{1,2,3,.....,299,300\right\}.$$

If the probability that $$x^{2} - y^{2}$$ is divisible by 3 is $$\frac{a}{b},$$ then what is the digit sum of $$a \times b$$?

Details and Assumptions:

1. Digit sum refers to the sum of all the digits of the number. For example, the digit sum of 123 is $$1+2+3=6.$$
2. $$a$$ and $$b$$ are co-prime numbers.
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