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# 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.

**Solution:**

Since the wheel of a road roller is cylindrical in shape,

In one revolution, the roller will cover an area equal to its lateral surface area.

Radius of the road roller r = 84/2 cm = 42 cm

Length of the road roller, h = 1 m = 100 cm

In 1 revolution, area of the road covered = 2πrh = 2 × 22/7 × 42 × 100

= 26400 cm² = 2.64 m²

In 750 revolutions area of the road covered = 750 × 2.64 m² = 1980 m²

**☛ Check: **NCERT Solutions for Class 8 Maths Chapter 11

**Video Solution:**

## 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

Maths NCERT Solutions Class 8 Chapter 11 Exercise 11.3 Question 9

**Summary:**

A road roller takes 750 complete revolutions to move once over to level a road. If the diameter of a road roller is 84 cm and length is 1 m, the area of the road is 1980 m².

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