Mice consumed a circular hole in a slice of cheese. The cheese has the shape of a circular cut with a radius of 20 cm and an angle of 90 degrees. What percentage of the cheese ate mice if they made 20 holes with a diameter of 2 cm?

Correct answer:

f =  20 %

Step-by-step explanation:

r=20 cm D2=2 cm r2=D2/2=2/2=1 cm n=20  S=π r24=3.1416 2024314.1593 cm2 S2=n π r22=20 3.1416 1262.8319 cm2  f=100 S2S=100 62.8319314.1593=20%

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