Question

PLEASE CHECK MY ANSWER <3 ~ the diameter of the base of a right cone is 12m . The total surface area of the cone is 306^cm2.
What is the length of the slant height ?
1) 45 cm
2) 36 cm
3 13.5 cm < my answer
4) 27 cm

Answer 1

How did you get that?

Answer 2

AHHH I meant to say my answer was 45cm ;-; sorry!

Answer 3

You were right the first time

Answer 4

But when I plugged it into SA = πr² + πrs
I got 45?

Answer 5

Ahh now im lost >~< I thought it was 13.5 < but my friend told me it was wrong and now I got 45

Answer 6

diameter is 12 meters.

Answer 7

or 12 cms

Answer 8

i doubt ,it can not be meters.

Answer 9

i consider diameter=12 cms
r=12/2=6
\[surface~area=\pi r^2+\pi r l\]
\[\pi *6^2+\pi*6*l=306,6*\pi \left(\pi+l \right)=306,\pi \left( \pi+l \right)=\frac{ 306 }{ 6 }=51\]
\[\pi+l=51\times \frac{ 7 }{ 22 }=16.23,l=16.23-\pi=16.23-\frac{ 22 }{ 7 }=13.08\]

Answer 10

l=slant height=13.08 cms approx.13 cms