There are class $$A$$ and class $$B$$ in the fourth grade, and the number of students in class $$A$$ is $$\frac{5}{7}$$ of that of class $$B$$. If $$3$$ students were transferred from class $$B$$ to class $$A$$, the number of students in class $$A$$ would be $$\frac{4}{5}$$ of that of class $$B$$. How many students are there in class $$A$$ right now? 
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