Question

What is the surface area of a sphere with radius 6?

Answer 1

A. 288 units2
B. 36 units2
C. 216 units2
D. 144 units2

Answer 2

Isnt it B :c I want to be sure.

Answer 3

use the formula

SA = 4*pi*r^2

Answer 4

it looks like they want the answer in terms of pi, so ignore that and stick it onto the final answer when you use a calculator

Answer 5

452.16 is what i got but its not there im so confused

Answer 6

That is absolutely right !!!

Answer 7

Good work!

Answer 8

Yes but it isnt there :(

Answer 9

the answer is one of these: A. 288 units2 B. 36 units2 C. 216 units2 D. 144 units2

Answer 10

They want you to do the other part of the computation only, and attach pi on the end

Answer 11

How do i do that?

Answer 12

ya so dont multiply by 3.14

Answer 13

(but as you point out, it isn't actually on the answers listed).

so you just do 4*pi*r^2 and find the answer that matches.

and then snicker about the poor question writing :-)

Answer 14

sorry, you do 4*r^2...

Answer 15

144?

Answer 16

144pi is the answer

Answer 17

yes :)

Answer 18

right. 144*3.14 = the number you got.

Answer 19

Thank you guys i was about to crack my head open!

Answer 20

yw :)

Answer 21

as you go on in math, you'll often find that it's advantageous to keep your answers like 144pi instead of 452.16...looking at the latter, you can't really tell that pi was a factor, right? Depending on what you are going to do with the answer, you might want to know that.

Answer 22

It's easy to turn 144pi into a decimal if you need it, but hard to recognize the reverse!

Answer 23

Yes your right,this was my last problem for Geometry (Thank GOD) but ill keep that in mind when starting Algebra 2. Thanks :)

Answer 24

Must feel good to be finishing off a big chunk of work like that, congratulations!

Answer 25

Take a 10 minute break before you get out the algebra book :-)