if 450 is the 100%, 600 - 450 = 150, thus, what is 150 in percentage off of 450?
[tex]\bf \begin{array}{ccllll}
amount&\%\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
450&100\\
150&x
\end{array}\implies \cfrac{450}{150}=\cfrac{100}{x}[/tex]
solve for "x".
