Verified answer

Answer:

1244.57 m²

Explanation:

Diameter is 24m and the slant height of the cone is 21m.

The total surface area of the cone is the sum of the curved surface area and area of the base which is a circle.

Curved surface area of a right circular cone of base radius 'r' and slant height 'l' is πrl.

Total surface area of the cone = πrl + πr2 = πr (l + r )

Diameter, d = 24m

Radius, r = 24/2m = 12m

Slant height, l = 21 m

Total surface area of the cone = πr (l + r )

= 22/7 × 12 m × (12 m + 21 m)

= 22/7 × 12 m × 33 m

= 8712/7 m²

= 1244.57 m²

Thus, total surface area of the cone = 1244.57 m²

Answer:

1244.57m²

Explanation:

formula, T = π(D/2) ((D/2) + l)

so plugging in values,

answer= 1244.57m²