There are $$6$$ factors of $$5$$ when you prime factorise~ $$1\times 2\times 3\times 4\times 5\times 6\times \cdots \times 25$$. 
How many $$0$$\textquotesingle s does the product of $$1\times 2\times 3\times 4\times 5\times 6\times \cdots \times 25$$ end with? 
[1] $$5$$ 
[2] $$6$$ 
[3] $$10$$ 
[4] $$12$$ 