OG2015 PS The figure above shows
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- lionsshare
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- yasirnasir
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I think it is 57Ï€ or option D.
If the circle and the path are taken together then the radius becomes 8 feet plus 3 feet = 11 feet
Formula to calculate the area of circles is: π r^2
By calculating the total area, it will be 121Ï€ . Now, if we calculate the area of the circle only then it be 65Ï€ . By subtracting the circle area from total area, we will have the area of the path i.e. 121Ï€ - 65Ï€ = 57Ï€ .
If the circle and the path are taken together then the radius becomes 8 feet plus 3 feet = 11 feet
Formula to calculate the area of circles is: π r^2
By calculating the total area, it will be 121Ï€ . Now, if we calculate the area of the circle only then it be 65Ï€ . By subtracting the circle area from total area, we will have the area of the path i.e. 121Ï€ - 65Ï€ = 57Ï€ .
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- Jay@ManhattanReview
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The radius of the outer edge of the path = 8 + width of the flower bed (= 3)
The radius of the outer edge of the path = 8 + 3 = 11 feet
Area of the path = Area of the outer circle of the path - Area of the inner circle of the path = π .(11)^2 - π .(8)^2 = 121π - 64π = 57π sq feet
The correct answer: D
Hope this helps!
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- Jeff@TargetTestPrep
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The circular path (i.e., the shaded region) is called an annulus in geometry. Basically an annulus is a ring-shaped figure bounded by two concentric circles. To find the area of an annulus, we use the following formula:
Ï€(R^2 - r^2)
where r is the radius of the inner circle and R is the radius of the outer circle.
We know:
R = 8 + 3 = 11 feet
r = 8 feet
Plugging into our equation, we have:
area = π(11^2 - 8^2)
area = π(121 - 64)
area = 57Ï€
Answer: D
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