Question

If $\frac{m}{n}=\frac{1}{2}$ Then $m:n=1:2$
Then is $m=1$ and $n=2$ ?

Answer 1

$\frac{m}{n}=\frac{1}{2}\Rightarrow m:n=1:2$

but it does not mean that $m=1$ and $n=2$.

It means that $m$ and $n$ have common divisor.