Question

4. Pipes A, B and C can fill a tank in 10, 15 and 30 hours,
respectively. D is an emptying pipe which alone can
empty the full tank in x hours. A, B and C are opened
together for 3 hours and then closed. Now D is opened
which alone empties the tank in 30 hours. What is the
value of x?
(
(a) 40
(b) 60
(c) 50
(d) 45
​

Answer 1

Step-by-step explanation i don't no what is. answer ok

Answer 2

Answer:

I hope it will help you 3