Question

circumference of base of cone is 220/7 cm and slant height is 13 cm. find total surface area of cone​

Answer 1

GiveN :-

• Circumference of base of cone is 220/7 cm .
• Slant height of the cone is 13 cm .

To FinD :-

• The TSA of cone .

AnsweR :-

We know that the circumference of the base of cone is 220/7 cm . And the circumference of circle is 2πr .

Atq,

⇒ 2 π r = 220/7 cm

⇒ 2 × 22/7 × r = 220/7 cm

⇒ r = 220 × 7 × 2 / 22 × 7 cm

⇒ r = 20 cm .

Hence the radius is 20 cm .

Now , TSA of cone is given by ,

$\large\boxed{\boxed{\red{\sf TSA_{cone}=\pi r ( l + r ) }}}$

⇒ TSA = π r ( l + r )

⇒ TSA = π r ( 20 cm + 13 cm )

⇒ TSA = 22/7 × 20 cm × 33cm .

⇒ TSA = 2074.28 cm² .

Hence the TSA of cone is 2074.28 cm².

$\Large{\boxed{\pink{\sf TSA_{cone}= 2074.28cm^2}}}$