# This looks easy to me...

Let $S = 5 \times 10 \times 15 \times 20 \times 25 \times 30 \times \ldots \times 1000$Let $$x$$ be the number of zeros at the end of $$S$$. Now,let $T = 10 \times 20 \times 30 \times 40\times \ldots \times 1000$Then, let $$y$$ be the number of zeros at the end of $$T$$.$$\frac{x}{y}$$ can be expressed as $$\frac{a}{b}$$,where $$a$$ and $$b$$ are positive, coprime integers.Find $$\frac{ab}{31}$$.

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