A hemispherical bowl has a 21 cm radius. It is to be painted inside as well as outside. The cost of painting it at the rate of ₹0.05 per cm2 and assuming that the thickness of the bowl is negligible, is: (Use =)
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. ₹277.20.
Radius = 21 cm
Area to paint = 4πr2
⇒ 4 × × 212 = 5544 cm2
Cost = 5544 × 0.05 = ₹277.20