The volume of a piece of drainpipe is 25 litres. If the diameter of the pipe is 5cm, how long is it? Give your answer in metres to 2 decimal places. (Remember, 1 litre = 1000cl, 1cl = 1cm^3)

Question

jigglypuff314 · Answer

hi, do you still need help with this?

scarlettthecamel · Answer

yes @jigglypuff314

jigglypuff314 · Answer

well if the diameter is 5
then the radius would be 2.5 right? :)

scarlettthecamel · Answer

yes i have had other people say that but i don't get how the radius has to do with it

scarlettthecamel · Answer

is it becoz of pi r^2

jigglypuff314 · Answer

yes :)
volume of pipe = pi r^2 L

scarlettthecamel · Answer

okay so how do i use this to get to the length

jigglypuff314 · Answer

from that equation  L = V / (pi r^2)

where V = 25 * 1000
and  r = 2.5

scarlettthecamel · Answer

okay

jigglypuff314 · Answer

so  L = (25000)/ (pi (2.5)^2)

scarlettthecamel · Answer

thanks so what does '/' mean?

jigglypuff314 · Answer

oh sorry xD
it means division, divide

scarlettthecamel · Answer

oright thanks haha!

scarlettthecamel · Answer

so would it be 1273.2

scarlettthecamel · Answer

@jigglypuff314

jigglypuff314 · Answer

yes, that's what I got :)
sorry for the late reply