Q. 134.0( 37 Votes )

# Find the cost of painting 15 cylindrical pillars of a building at Rs. 2.50 per square metre if the diameter and height of each pillar are 48 cm and 7 metres respectively.

Answer :

It is given in the question that,

Diameter of the cylindrical pillars = 48 cm

Hence,

The radius of the cylindrical pillars =

= 24 cm

= 0.24 m

Height of the cylindrical pillars = 7 m

Now,

Lateral surface area of one pillar =

=

= 10.56 m^{2}

Now,

The surface area to be painted = total surface area of 15 pillars

= 15 × 10.56

= 158.4 m^{2}

Therefore,

The total cost of painting = Rs(158.4 × 2.5)

= Rs 396

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