Question

there are 20 cylindrical pillars in a building the diameter of each pillar is 50 cm and height is 90 centimetre find the total cost off white washing the little surface area of all pillars rupees 2percm square​

Answer 1

Answer:

It is given that

Diameter of one pillar =50cm=0.5m

So the radius of one pillar =0.5/2=0.25m

Height of one pillar =4m

We know that

Lateral surface area of one pillar =2 πrh

By substituting the values

Lateral surface area of one pillar =2×(22/7)×0.25×4

So we get

Lateral surface area of one pillar =6.85 m

2

So the lateral surface area of 20 pillars =20×6.285=125.714 m

2

It is given that the cost of cleaning =Rs.14 per m

2

So the cost of cleaning 125.714 m

2

=Rs.(14×125.714)

We get

Cost of cleaning 125.714 m

2

=1760

Therefore, the cost of cleaning 125.714 m

2

is Rs.1760.

Step-by-step explanation:

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