The curved surface area and the slant height of a right circular cone are 858 cm2 and 13 cm respectively. Find its diameter (in cm).

42 cm 40 cm 44 cm 41 cm

42 cm

The curved surface area of right circular cone = \(\pi \)rl \(\frac{22}{7}\)× r × 13 = 858 r = \(\frac{858 × 7}{22 × 13}\) r = 21 Diameter = 2r = 2 × 21 = 42 cm