The radius of a roller is 14 cm and its length 20 cm. It takes 235 complete revolutions to move once over to level a playground. Find the area of the playground.(Use π=22/7)
Answer & explanation
Correct answer: option 4
We know that,
Curved surface area of cylinder = 2πrh
We have,
Radius of roller = 14 cm
Length = 20 cm
Curved surface area of roller = 2 × \(\frac{22}{7}\) × (14) × (20) = 1760 cm².
Now, area of the playground = 235 × 1760
= 4136 × 102 cm²