Given the following data for two compounds $Sn{O}_2$and $SnO$. What is the whole number ratio of the oxygen of $SnO$ to the oxygen of $Sn{O}_2$. Does this follow the law of multiple proportions?

Ratio of oxygen of $SnOtoSn{O}_2$is $\frac{13.5}{27.1}=\frac{1}{2}$

According to law of multiple proportions, ratio of masses of an element that combine with fixed mass of another element must be a simple whole number ratio.

Element with fixed mass = $Sn$

Element with different combining ratio = oxygen

The law of multiple proportion is obeyed.