Question

Playground offers kids fresh air, friends, fun and exercise. But it is important to make sure that improper surfaces, equipment and unsafe behaviour don't ruin the fun. In this order Raigarh Nagar Nigam announced an online tender for levelling the roads of ABC Park A contractor gets this work from Raigarh Nagar Nigam. Contractor has a roller of diameter of 42 cm and its length is 78 cm. It takes 300 revolutions to move once over to level the playground. Consider the above problem and answer the following questions
(a) Find the area (in m²) covered in one revolution.
(b) If the area covered in one revolution is 5.168 m², then find the area (in m²) of playground
(c) If area of playground is 3600 m², then find the area covered in one revolution.​

Answer 1

r=42cm

h=78cm

a)area covered in one revolution=2πrh

=2×(22/7)×42×78=44×6×78=20592cm²=2.0592m²

b)formula for csa=2πrh

c)area of playground total revolution×c.s.a=500×2.0592=1029.6m²

d)area of playground= 300×5.168=1550.4m²

e)area of one revolution=area÷total revolution=3600÷300 = 12m²