Question

A cylindrical tin with diameter of base $20cm$ and height $25cm$ is open at the top. Find the cost of painting the tin at $Rs.300$ per $m^2$. (Use $\pi =3.14$)

• A. $Rs.56.57$
• B. $Rs.56.51$
• C. $Rs.55.52$
• D. $Rs.56.50$

Answer 1

The correct option is A $Rs.56.57$

$r=10cm,h=25cm$
Total surface area$=2\pi r(r+h)=2\pi \left(10\right)(10+25)=700\pi =2200c{m}^2$
$=0.22m^2$
Area of circle$=\pi {10}^{2}c{m}^2=0.0314m^2$
Area of tin$=0.1885$
Cost of painting of tin $Rs.300per{m}^2=0.1885\times 300=Rs.56.57$