if 5000 gets increased by 200, then you end up with 5200.
if 900 gets increased by 200, then it'd be 1100.
so in short, if we take 5200 to be the 100%, what is 1100 in percentage from it?
[tex]\bf \begin{array}{ccll}
amount&\%\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
5200&100\\
1100&p
\end{array}\implies \cfrac{5200}{1100}=\cfrac{100}{p}\implies p=\cfrac{1100\cdot 100}{5200}[/tex]
