Answer :
To solve this problem, we have to use the following proportion
[tex]\frac{90}{z}=\frac{30x}{200x}[/tex]Where z represents 200% of the number
[tex]\begin{gathered} \frac{90}{z}=\frac{3}{20} \\ z=\frac{90\cdot20}{3} \\ z=600 \end{gathered}[/tex]