SOLUTION: A large pipe can fill a tank in 10 minutes, and a smaller pipe can fill the tank in 20 minutes. How long will it take to fill the tank if the both pipes are used at the same time?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A large pipe can fill a tank in 10 minutes, and a smaller pipe can fill the tank in 20 minutes. How long will it take to fill the tank if the both pipes are used at the same time?       Log On


   



Question 411440: A large pipe can fill a tank in 10 minutes, and a smaller pipe can fill the tank in 20 minutes. How long will it take to fill the tank if the both pipes are used at the same time?
Thank you,
--Nienyotza

Answer by sudhanshu_kmr(1152) About Me  (Show Source):
You can put this solution on YOUR website!
if both pipes are used then in one minute tank will fill ( 1/10 - 1/20 ) portion
it is 1/20 portion...

as 1/20 portion of tank fill in 1 minute.

so, for 1 complete portion 1 / (1/20) = 20


so, 20 minutes.....