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Katlin is choosing between two circular wall clocks one has the radius of 5 inches while the other one has a radius of 6 inches.How much more wall space will the clock with a radius of 6 inches cover?

Plz help i dont get any of these type of questions T-T

User Bao Le
by
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1 Answer

8 votes

Answer:

Exact:
11 \pi~in.^2

Approximate:
34.6~in.^2

Explanation:

The spaces the clocks occupy on the wall are the areas of the clocks.

The clocks are shaped like circles, so use the formula for the area of a circle to find the two areas. Then subtract the smaller area from the larger area.


A_(circle) = \pi r^2

Larger clock, r = 6 in.


A_(large~clock) = \pi * (6~in.)^2 = 36 \pi ~in.^2 = 113.1~in.^2

Smaller clock, r = 5 in.


A_(small~clock) = \pi * (5~in.)^2 = 25 \pi ~in.^2 = 78.5~in.^2

Difference in areas:

Exact:
36 \pi~in.^2 - 25 \pi~in.^2 = 11 \pi~in.^2

Approximate:
113.1~in.^2 - 78.5~in.^2 = 34.6~in.^2

User Frank Roth
by
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