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Mensuration | Exercise 11.3

Question 18

Q9) A road roller takes 750 complete revolutions to move once over to level a road. Find the area of the road if the diameter of a road roller is 84 cm and length is 1 m.

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Solution 9:

A road roller is cyclindrical in shape, hence one revolution is equal to the curved surface area of cylinder.

1 revolution = 2\pi rh

r\ =\ \frac{84}{2\ }cm\

= 42cm

h = 1m = 100cm

CSA = 2\times\frac{22}{7}\times42\times100

= 26400 cm\ ^2

750 revolutions of road roller completely level a road.

Area covered by road roller = 750\times26,400\ cm^2

= 19800000cm\ ^2

= 1980\ \ m^2

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Our top 5% students will be awarded a special scholarship to Lido.

subject-cta

Question 18

Q9) A road roller takes 750 complete revolutions to move once over to level a road. Find the area of the road if the diameter of a road roller is 84 cm and length is 1 m.

Looking to do well in your science exam ? Learn from an expert tutor. Book a free class!

Solution 9:

A road roller is cyclindrical in shape, hence one revolution is equal to the curved surface area of cylinder.

1 revolution = 2\pi rh

r\ =\ \frac{84}{2\ }cm\

= 42cm

h = 1m = 100cm

CSA = 2\times\frac{22}{7}\times42\times100

= 26400 cm\ ^2

750 revolutions of road roller completely level a road.

Area covered by road roller = 750\times26,400\ cm^2

= 19800000cm\ ^2

= 1980\ \ m^2

Our top 5% students will be awarded a special scholarship to Lido.

subject-cta
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