Question

Find the cost of painting curved surface area of 12 pillars each of diameter 48 cm and height 7 m at the rate of rs.2.50 per m2

Answer 1

hey mate here is your answer

pillar = cylinder

d=48cm so, r=48/2= 24cm

h=7m=7×100=700cm

csa of cylinder=

$2\pi \times r \times h$

$2 \times 22 \div 7 \times 24 \times 700$

$105600cm {}^{2}$

or

$105600 \div 100$

$1056m {}^{2}$

csa of 12 cylinder =

$12 \times 105600$

$12672m {}^{2}$

cost of painting=

$12672 \times 2.5$

$31680.0 \: rupees$