Number of square feet of wall painted in 1 hour is 243 square feet. Therefore, option C is the correct answer.
Given that, it takes Zach 10 minutes to paint [tex]40\frac{1}{2}[/tex] square feet of his bedroom wall.
The unitary method is a technique for solving a problem by first finding the value of a single unit, and then finding the necessary value by multiplying the single unit value.
Here, [tex]40\frac{1}{2}[/tex] square feet = 40.5 square feet
Rate at which he paints the wall =40.5/10
= 4.05 square feet per minute
As we know 1 hour =60 minutes
Now, number of square feet
= 4.05×60
= 243 square feet
Number of square feet of wall painted in 1 hour is 243 square feet. Therefore, option C is the correct answer.
To learn more about the unitary method visit:
brainly.com/question/22056199.
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