Pipe A and Pipe B together can fill the tank in 60 min.?

Question

 Efficiency of Pipe A , B and C are in the ratio of 2 : 3 : 1. Pipe A and Pipe B are the inlet pipes whereas Pipe C is the outlet pipe. Find out the time taken by A and C together to fill the tank?

(a) 240 min

(b) 280 min

(c) 300 min

(d) 320 min

(e) 360 min

Answer 1

Favourite answer

Pipe A fills the tank at a rate of 2/5 tank per 60 min.

Pipe B fills at 3/5 tank per 60 min.

So pipe C `emptied it at 1/5 tank per 60 min.

Pipes A and C fill it at a rate of 2/5 - 1/5 = 1/5 tank per 60 min which would be 1 tank per 300 min.

IMO anyway

Answer 2

if " 5 " somethings require 60 minutes then " 1 " somethings would require 300 minutes