Question

The diameter of a 120cm long rollar is 84cm. IT takes 1000 complete revolutions moving once over to level a playground. What is the area of the playground ?​

Answer 1

Answer:

Step-by-step explanation:

Radius of the roller (r) = 84/ 2 cm = 42 cm  

Length of the roller (h) = 120 cm  

Curved surface area of the roller = 2πrh  

= 2 × 22/ 7 × 42 × 120 cm2 = 44 × 720 cm2= 31680 cm2  

∴ area covered by the roller in 1 revolution = 31680 cm2  

∴ area covered by the roller in 1000 revolutions = 31680 × 1000 cm2 = 31680000 cm