Find the curved surface area of a cone having base diameter 42 cm and height 20 cm. $\left(π=\frac{22}{7}\right)$
Answer & explanation
Correct answer: option 3
Given,
Diameter of the cone = 42 cm
Radius of the base of the cone = 21 cm
Slant height of the cone,
l2 = r2 + h2
l2 = 212 + 202
l = 29 cm
Curved surface area of cone = πrl
\(\frac{22}{7}\) × 21 × 29 = 1914 cm2