# List 'em Out!

Number Theory Level 4

Two numbers $$x$$ and $$y$$ are chosen at random without replacement from the first $$30$$ natural numbers. the probability that $$x^{2} - y^{2}$$ is divisible by $$3$$ is given by $$\frac{a}{b}$$. where a and b are co-prime to each other. Then $$a+b$$ is equal to

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