Answer:
The height of her screen on her drawing must be 30 inches.
Step-by-step explanation:
The scale factor is obtained by dividing the drawn width by real width of the movie screen:
[tex]k = \frac{9\,in}{60\,ft}[/tex]
[tex]k = \frac{3\,in}{20\,ft}[/tex]
The drawn height of movie screen is the product of the scale factor and the real height of the movie screen:
[tex]h_{s} = \left(\frac{3\,in}{20\,ft} \right)\cdot (200\,ft)[/tex]
[tex]h_{s} = 30\,in[/tex]
The height of her screen on her drawing must be 30 inches.