Question

22. If slant height of the cone is 21cm and diameter of base is 24 cm. The total surface area of cone
is: *
​

Answer 1

Answer:

Slant height of cone is l = 21 m

Diameter of its base is d = 24 m

So, radius of its base is r = d/2 = 12 m

Now, the total surface area of cone is

area = πrl + πr2

area = π(rl + r2)

area = π(12×21 + 122 )

area = π(252 + 144)

area = (22/7) ×396

So total area is = 1244.5714 m2

Answer 2

Answer:

tsa of cone = πrl+πr²

=22/7×12×21+22/7×12×12

=792+452.5

=1244.5 cm²