Question

The pillars of a temple are cylindrical shaped. if each pillar has a circular base of radius 20 cm and height 10 m, find the cost of painting 14 such pillars @ Rs 20/m?? ​

Answer 1

Answer:

csa of 1 pillar = 2pi r h

=2×22/7×20×10 = 22/7×400

csa of 14 pillars=22/7×400 ×14 = 17600cm^2 =176m^2

cost of 1m^2 =rs20

cost of 176m^2= 176×20= Rs 3520

Answer 2

Step-by-step explanation:

Paint will be applied only on the curved area of the cylinder.

Curved Surface Area of cylinder =

$2\pi \times r \times h$

= 2 × 3.14 × 0.20 × 10 = 12.56m²

Curved Surface Area of 14 such pillars = 14 × 12.56 = 175.85 m²

Cost of painting = Rs 20 /m = Rs 400 /m²

Cost for painting 14 pillars = 175.85 × 400 = Rs 70,340