Question

to the nearest whole number. what is the surface area of a sphere with a volume of 140 cm^3

Answer 1

:-) You should be a wiz at this now.

Answer 2

lol should be! can be! aint be though lol

Answer 3

You know that 3V = 4 pi r^3, right?

Answer 4

haha ummmmm..........yea?????

Answer 5

now i do

Answer 6

So what's r?

Answer 7

11.1

Answer 8

4/3 *pi r^3=v
r=[v*(3/4)(1/pi)]^1/3
surface area=4*pi*r^2

Answer 9

I'm not checking it, I'll just assume you did it right.

Now put r in the formula you had before for SA.

Answer 10

mmm ok

Answer 11

ie SA = 3*V/r

Answer 12

umm yah wrong!!!

Answer 13

fother mucking volume an surface area!!!!! i hate it

Answer 14

Just check you calculation, did you use a calculator?

Answer 15

Is r 3.22?

Answer 16

So 130.43 for SA? (I could have made a mistake as well).

Answer 17

the closest answer choice is 130 so i think your right so yeah i hope tis is my last volume ?

Answer 18

I think your problem is not with the surface area / volume, it seems that u are rushing your calculations or making a mistake with the calculator.

Just go slowly, check as you go, it will save you time in the end.

Answer 19

ok so what is the formula for surface area? SA=???

Answer 20

SA = 3times the volume divided by the radius = 3V/r

Answer 21

This assumes you know the radius....

Answer 22

You understand? You have to find the radius with one formula and then the surface area with another.

Answer 23

ok an yeah i understand

Answer 24

Just to make it absolutely clear:-

Vol = 4*pi*r^3 over 3 (so if you know the volume, you can calculate the radius).

Answer 25

oh ok thnx

Answer 26

hey im findin the surface area of a cylynder now does the formula change?

Answer 27

Including the top and bottom?

Answer 28

top bottom and the sides

Answer 29

Well, it's 2 pi r h (for the side) + 2 pi r^2 (for top and bottom together).

Answer 30

yeag lol i jus found that out i got it from here i think