Question

Rahul a circular path of radius radius 28 may there is a road of uniform width 7m outside it find the area of the road use

Answer 1

correct question: around a circular path having radius 28 m , there is a road outside it having width 7m . Find the area of the road.

Solution:
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let radius of the inner circle r = 28 m

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since , the width of road = 7 m

outer circle:
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Find the radius of outer circle:

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radius of outer circle R = radius of inner circular path + width of the road

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= 28m + 7m = 35 m

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Find the area of the road:
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area of the road

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= area of outer circle - area of inner circle

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= πR^2 - πr^2

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= π ( R^2 - r^2 )

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= π [ (35)^2 - ( 28 )^2 ]

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= π ( 1225 - 784 )

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= 441π = (441 × 22 ) / 7

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= 9702 ÷ 7 = 1386m^2

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Answer:
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area of the road = 1386 m^2
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