what is the raduis of cylindrical object if it height is 10 m and a volume of 1538.6 cubic meter?

Question

anonymous · Answer

$$r = \sqrt(V/\pi*H)$$

just put H = 10, and V that horrible number..and take pi ~ 3.14

anonymous · Answer

because $$V = BH,  B = r^2H \rightarrow V = r^2 \pi H$$

anonymous · Answer

B = r^2 * pi, sorry

anonymous · Answer

is there a simple way? im only 2nd year

anonymous · Answer

ok, I'll do the whole procedure :) just a sec :)

anonymous · Answer

Fist, basic expression for cylinder's volume is:
V = B * H
V - volume, given, 1538.6
B - are of circle in the base
H - height, here 10m

Since base is a circle, formula for are of circle is:
$$B = r^2 \pi$$

just put that together..
$$V  = B H = r^2 \pi H$$
now, lets replace numbers
$$1538.6 = r^2 \pi * 10$$
put 10 and $$\pi$$ on the other side of "=" (if its up on one side, it goes down on the other)
$$r^2 = V / (\pi H)$$
$$r^2 = 1538.6 / (3.14 * 10)$$
$$r^2 = 1538.6 / 31.4$$

so, calculate that number...and r is square root of that number :)
there just isn't any simpler way :)

anonymous · Answer

am, ok... and there is 7 remaining questions, cn u help me?