Question

the radius and height of a cone are in the ratio 5:12 if its volume is 314 cm^3,find its slant height and c.s.a.π=3.14

Answer 1

let proportionality constant =x
radius =5x and height =12x

now,
volume of cone =πr^2h/3
314=3.14(5x)^2.(12x)/3
100=25 x 4(x^3)
x=1
hence,
radius =5cm
height =12 cm
so,
slant height=√{(12)^2+(5)^2}=13cm
now,
cross section area =πr^2
=3.14 x 5 x 5 =78.5 cm^2

Answer 2

Answer:

• 78.5 cm^2.

Step-by-step explanation:

volume of cone=(=\<) pi r ^2

314=3.14(6x)^2.(13x)3

100=25 into or multiple 4(x^3)

x=1

radius =5cm

height =12cm

{root(12^2)+(5)^2}=13cm

(=\<) pi r ^2

=3.14 multiple 5 multiple 5 multiple=78.5cm^2