A hemispherical bowl has 3.5 cm radius. It is to be painted inside as well as outside. Find the cost of painting it at the rate of ₹15 per 10 cm². (Use π = 22/7.)

Correct option is C

Given:

Radius of the hemispherical bowl = 3.5 cm

Cost of painting = ₹15 per 10 cm²

​$$π = \frac{22}{7}$$​​

Formula Used:

Curved Surface Area of Hemisphere = 2 × π × r²

Base Area of Hemisphere = π × r²

Total Area to be painted = 2 × Curved Surface Area 

Solution:

Curved Surface Area =  $$2 ×\frac{ 22}{7 }× 3.5 × 3.5 = 77 cm²$$​​

Total Area to be painted = 77 + 77  =  154 cm²

Cost of painting =  $$154× \frac{15 }{10} = ₹231$$​​