Question

A road roller is 140cm long .Its diameter is 84 cm . It takes 1000 complete revolutions once over to level the road. Find the cost of levelling the road at Rs 50 per 100 square metres

Answer 1

area covered in one complete revolution =surface area of road =2pi.r.h
=2 x 22/7 x 42 x 140 cm^2
=12 x 22 x 140 cm^2
=36960 cm^2

covered area in 1000 revolution =1000 x surface area of road roller =36960 x 10^3 cm^3
=3696 m^2

now,
cost = surface area of roller x rate
=3696 x 50/100 =1848 Rs

Answer 2

Answer:

Step-by-step explanation:

area covered in one complete revolution =surface area of road =2pi.r.h

=2 x 22/7 x 42 x 140 cm^2

=12 x 22 x 140 cm^2

=36960 cm^2

covered area in 1000 revolution =1000 x surface area of road roller =36960 x 10^3cm^3

=3696 m^2

now,

cost = surface area of roller x rate

=3696 x 50/100 =1848 Rs