Answer:
75 cm
Explanation:
The distance of the screen varies inversely proportional to the area subtended.
[tex]\frac{d_1}{d_2}=\frac{A_2}{A_1}\\\frac{100}{200}=\frac{A_2}{150}\\A_2=75 cm[/tex]
When the distance is increased from the screen, the area would decrease to 75 cm.