Question

A roller has diameter 91cm and it is 130cm long.it takes 600 revolutions to level a playground .find cost of revelling at rate 37 paise pr square meter ​

Answer 1

Answer:

so it's lateral surface area so 2 pie r h ok

2*22/7*45.5*130

=37180

Answer 2

Answer:

Step-by-step explanation:

Clearly the roller is a right circular cylinder of height h=120 cm

and radius of its base =r=42 cm

∴ area covered by the roller in one revolution = curved surface area of the roller 

           =2×722​×42×120cm2=31680cm2

so, area covered by the roller is 500 revolution = (31680×500)cm2

                    =100×10031680×500​m2=1584m2

hence , cost of levelling the playground = 1584×10030​=Rs475.20