Three pipes X, Y and Z discharge three different chemicals A, B and C in a tank. The pipes can fill the tank in 20, 25 and 40 minutes respectively. What will be the proportion of chemical B in the tank, if all the pipes are open for 10 minutes?

Three pipes X, Y and Z discharge three different chemicals A, B and C

1.	Three pipes X, Y and Z discharge three different chemicals A, B and C in a tank. The pipes can fill the tank in 20, 25 and 40 minutes respectively. What will be the proportion of chemical B in the tank, if all the pipes are open for 10 minutes?
A.	4/7
B.	13/23
C.	8/23
D.	11/15
Answer» D. 11/15