Question

Find the number which bears the same ratio to $\frac{7}{33}$ that $\frac{8}{21}$ does to $\frac{4}{9}$.

Answer 1

$4=\frac{8}{2}$
$9=21\times \frac{3}{7}$
For$\frac{8}{21}\to \frac{4}{9},\frac{7}{33}\to \frac{a}{b}$ (let)
$a=7\times \frac{1}{2}=3.5b=33\times \frac{3}{7}=\frac{99}{7}\frac{a}{b}=\frac{3.5}{\frac{99}{7}}=\frac{24.5}{99}=\frac{49}{198}$