Question

Find the cost of painting cylindrical pillar of radius 7cm and height 0.1m at the rate of Rs. 20 per square cm, also find volume of cement used to build it.

Answer 1

Step-by-step explanation:

r = 7cm

h= 0.1m=10cm

CSA OF cylinder

$= 2\pi \times rh \\ = 2 \times \frac{22}{7} \times 7 \times 10 \\ = 440cm { }^{2}$

cost per cm² = 20

cost for 440cm²= 440*20= Rs. 8800

volume of cylinder

$= 2\pi {r}^{2} h \\ = 2 \times \frac{22}{7} \times {7} \times 7 \times 10 \\ = 3080 {cm}^{3}$