SOLUTION: Volume of 239 cubic cm and height of 6 cm, how do I find the radius? What is the formula? pkn@bellsouth.net

Algebra ->  Volume -> SOLUTION: Volume of 239 cubic cm and height of 6 cm, how do I find the radius? What is the formula? pkn@bellsouth.net      Log On


   

Question 946159: Volume of 239 cubic cm and height of 6 cm, how do I find the radius? What is the formula?
pkn@bellsouth.net
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

I guess you have a cylinder.
the formula for volume is:
V=+pi%2A+r%5E2+%2A+h
if V=239cm%5E3 and h=6cm, then we have
239cm%5Ecross%283%29%5E2=+3.14%2A+r%5E2+%2A6cross%28cm%29
239cm%5E2=+3.14%2A+r%5E2+%2A6
239cm%5E2=+18.84%2A+r%5E2+
239cm%5E2%2F18.84=r%5E2+
12.68577494692144cm%5E2=r%5E2+
r=sqrt%2812.68577494692144cm%5E2%29
r=3.561709553981268cm
r=3.56cm (approximately)

but, if you have a cone then:
V=+%281%2F3%29%28pi%2A+r%5E2+%2A+h%29
239cm%5E2=+%281%2F3%29%283.14%2A+r%5E2+%2A6%29
3%2A239cm%5E2=+18.84%2A+r%5E2+
717cm%5E2=+18.84%2A+r%5E2+
717cm%5E2%2F18.84=+r%5E2+
38.057cm%5E2=+r%5E2+
r=sqrt%2838.057cm%5E2%29+
r=6.17cm+