Question 10
Taps A and B fill an empty tank as follows:
• Together they fill it in 30 minutes.
• Running A for 12 minutes, then shutting A and running B for 42 minutes, also fills it.
How many minutes before B should A be opened so that the tank becomes full with equal amounts supplied by the two taps? Show your reasoning.
Practice convention: Each tap has a constant flow rate whenever it is open.
• Together they fill it in 30 minutes.
• Running A for 12 minutes, then shutting A and running B for 42 minutes, also fills it.
How many minutes before B should A be opened so that the tank becomes full with equal amounts supplied by the two taps? Show your reasoning.
Practice convention: Each tap has a constant flow rate whenever it is open.