A 15

B 20

C 25

D 40

]]>so, 1500/x – 1500/( x+ 10) = 5

x

Solving this we get x = 50

Emptying capacity : 50 + 10 => 60 m

]]>

then 6 min for P to reach 3/4th and 10 min for Q to take it to 1/4th.Thus 16 min.

so after 19+2*16=51 mins,it will be at 1/4th and then P fill it till 57th min and then in 3 min Q empty it by 3/20th so final answer: 3/4-3/20=12/20=3/5

]]>