Find the total surface area of a cone, if its slant height is 21m and

1.	Find the total surface area of a cone, if its slant height is 21m and diameter of its base is 24m.
Answer» It is given that Diameter of the cone = 24m Radius of the cone = 24/2 = 12m Slant height of the cone = 21m We know that Total surface area of a cone = πr (l + r) By substituting the values Total surface area of a cone = (22/7) × 12 (21+12) On further calculation Total surface area of a cone = (22/7) × 12 × 33 So we get Total surface area of a cone = 1244.57 m² Therefore, the total surface area of a cone is 1244.57 m².

Find the total surface area of a cone, if its slant height is 21m and diameter of its base is 24m.

Answer»

It is given that

Diameter of the cone = 24m

Radius of the cone = 24/2 = 12m

Slant height of the cone = 21m

We know that

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

By substituting the values

Total surface area of a cone = (22/7) × 12 (21+12)

On further calculation

Total surface area of a cone = (22/7) × 12 × 33

So we get

Total surface area of a cone = 1244.57 m²

Therefore, the total surface area of a cone is 1244.57 m².