SOLUTION: How should I do this problem; I don't know how to get the answer. I do know that the formula to find a sphere's volume is V=Bh & "big b" is the area of the base, or pi times the

Algebra ->  Volume -> SOLUTION: How should I do this problem; I don't know how to get the answer. I do know that the formula to find a sphere's volume is V=Bh & "big b" is the area of the base, or pi times the       Log On


   

Question 195543: How should I do this problem; I don't know how to get the answer. I do know that the formula to find a sphere's volume is V=Bh & "big b" is the area of the base, or pi times the radius squared. I do not recall doing this problem type in class. This is the problem:
The ratio between the volumes of two spheres is 27 to 8. What is the ratio between their respective radii?
A: 81:64
B: 9:8
C: 3:2
D: 27:16
Your help will be much appreciated, so thank you in advance! :D
Found 2 solutions by user_dude2008, ankor@dixie-net.com:
Answer by user_dude2008(1862) About Me  (Show Source):
You can put this solution on YOUR website!
Volume of Sphere:

Sphere 1: Volume = v1, radius = r1
Sphere 2: Volume = v2, radius = r2


















Ans: ratio is 3:2

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
I have no idea what he base of a sphere is!
:
The ratio between the volumes of two spheres is 27 to 8.
What is the ratio between their respective radii?
;
Vol of the sphere formula: V = %284%2F3%29%2Api%2Ar%5E3
:
Two radii: r1 and r2
:
27%2F8 = %28%284%2F3%29%2Api%2Ar1%5E3%29%2F%28%284%2F3%29%2Api%2Ar2%5E3%29
Cancel like terms:
27%2F8 = %28r1%5E3%29%2F%28r2%5E3%29
Find the cube root of both sides
3%2F2 = r1%2Fr2