How many hours would it take to fill the tank if both pipes are opened? I. The tank has a capacity of 400 litres. II. The pipe A takes 4 hours to fill the tank. III. The pipe B takes 6 hours to fill the tank.
A. Only I and II
B. Only II and III
C. All I, II and III
D. Any two of the three
Answer:B
How many hours would it take to fill the tank if both pipes are opened? I. The tank has a capacity of 400 litres. II. The pipe A takes 4 hours to fill the tank. III. The pipe B takes 6 hours to fill the tank.
A. Only I and II B. Only II and III C. All I, II and III D. Any two of the three
Explanation: II. A filled a quarter of the tank in one hour =Part of the tank filled in 1 hour by B = 1/6,1 hour of work (A + B) = 1/4 + 1/6 = 5/12,A and B will fill the tank in 12/5 hours, which is 2 hours and 24 minutes.As a result, II and III are required.