An ice cream cone has a radius of 2 cm and slant height of 5 cm. If 100 such cones are to be painted externally (excluding base), what is the total painted area?
Show answer & explanation
Correct answer: D
Explanation
Given:
Radius (r) = 2 cm
Slant height (l) = 5 cm
Number of cones = 100
By formula:
Curved surface area of a cone = πrl
Area of one cone = π × 2 × 5 = 10π
Area of 100 cones = 100 × 10π = 1000π
= 1000 × 3.14
= 3140 cm²