Question

(a) The diameter of the base of a right circular cone is 21 metres and height is 14 metres What will be the expenditure to colour the curved surface at the rate of Rs. 1.50 per square metre? 298​

Answer 1

Answer:

rs866.25

Step-by-step explanation:

So, the expenditure to colour the curved surface area at the rate of rs1.50 per sq-m =rs577.5×1.50=rs866.25. Hence the required cost =rs866.25.       Please mark me as the brainliest.

Answer 2

Base radius of the cone=10.5m. Axial height=14m

base:height ratio=3:4. Also, 3:4:5 is a basic pythagorean triplet. Thus slant height of the cone=5*14/4=17.5m. The curved surface of the cone=10.5*17.5*22/7=577.5sq-m.

Total cost of painting its curved surface=577.5*Rs.1.5=Rs.866.25