Question

A cone has a diameter of 7 cm and a slant height of 15.5 cm. What is the surface area of the cone?

Answer 1

Answer:66.5 cm2

Step-by-step explanation:

Answer 2

Answer:

Total surface area of the cone = 208.81 sq cm

Step-by-step explanation:

Diameter of the cone (d)  = 7 cm

Slant height (L) = 15.5 cm

1) The radius of the cone= Half of the diameter

= 7/2 cm = 3.5 cm

⇒ r = 3.5 cm

Now, Total surface area of the cone = $\pi r^{2} + \pi rl$

taking π = 3.14

We get $\pi r^{2} = 3.14 \times 3.5 \times 3.5 = 38.465 cm^{2}$

and  πrl = 3.14 x 3.5 + 15.5 = 170.345

So, Total surface area of the cone  = 38.465 + 170.345 = 208.81 sq cm