Ask your own question, for FREE!
Mathematics 21 Online
OpenStudy (heyitslizzy13):

can anyone explain this thoroughly ?

OpenStudy (heyitslizzy13):

OpenStudy (anonymous):

i think i can

OpenStudy (anonymous):

first either we need a variable for the radius of the sphere, or else we can give it a number your choice, it makes no difference

OpenStudy (heyitslizzy13):

r?

OpenStudy (anonymous):

ok that is a good choice

OpenStudy (anonymous):

if the radius of the sphere is \(r\) do you know the volume of the sphere (in terms of \(r\)?)

OpenStudy (heyitslizzy13):

i have no idea

OpenStudy (anonymous):

ok then i will tell you although a quick google search gives it instantly it is \[A=\frac{4}{3}\pi r^3\]

OpenStudy (anonymous):

if the radius of the sphere is \(r\) then the length of the side of the cube is evidently \(2r\) what is the volume of the cube?

OpenStudy (heyitslizzy13):

a^3?

OpenStudy (anonymous):

yeah but \(a=2r\)

OpenStudy (heyitslizzy13):

8r^3?

OpenStudy (anonymous):

so \[(2r)^3=8r^2\] is volume of the cube right

OpenStudy (anonymous):

then divide and you are done the \(r^3\) will cancel when you do that

OpenStudy (heyitslizzy13):

i'm so confused :/

OpenStudy (anonymous):

they want the ratio of the volumes right?

OpenStudy (heyitslizzy13):

yes

OpenStudy (anonymous):

the cube has volume \(8r^3\) and the sphere has volume \(\frac{4}{3}\pi r^3\)

OpenStudy (anonymous):

the ratio is \[\huge \frac{8r^3}{\frac{4}{3}\pi r^3}\]

OpenStudy (anonymous):

cancel the \(r^3\) and simplify the compound fraction

OpenStudy (heyitslizzy13):

6/pi ?

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!