Question

4. 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.​

Answer 1

Answer:

750× lateral surface area of cylinder

=750×2πrh

Given,  d=84cm⇒r=42cm→10042​m

h=1m

=750×2×722​×10042​×1

=1001500×132​

=1980m^2

Step-by-step explanation:

Answer 2

Given:- A road roller takes 750 complete revolutions to move once over to level a road.the diameter of a road roller is 84 cm and length is 1m.

To Find:- the area of the road.

Answer:- Number of revolutions taken by roller = 750 . Diameter of roller = 84cm . So radius ( r ) will be 84cm/2 = 42cm .

Lenght of roller = height = 1m = 100cm .

Now , Lateral Surface area of cylinder = 2πrh

=> LSA = 2πrh

=> LSA = 2 × 22/7 × 42cm × 100cm.

=> LSA = 26400 cm² .

Now number of revolutions is 750 . So total area

= No.of revlotions × LSA

= 750 × 26400cm²

= 198,00,000 cm²

= 198,00,000/10,000 m²

= 1980 m².

Hence the area of the road is 1980 m².