Question

If 5/7 of x is 5/21 then what's x?

Answer 1

$\frac{5}{7} \: \: \: of \: \: \: x = \frac{5}{21} \\ = > \frac{5x}{7} = \frac{5}{21} \\ = > 5x = \frac{5}{21} \times 7 \\ = > 5x = \frac{5}{3} \\ = > x = \frac{5}{3} \times \frac{1}{5} \\ = > x = \frac{1}{3}$

Answer:

$x = \frac{1}{3}$

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