Two pipes opened alternately for one hour each: time to fill or empty

This type of question, asked 2 times: 3 Mar 2023 Tier II, 20 Jan 2025 Tier II. All 2 questions below, oldest first.

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Question 1
3 Mar 2023 Tier II
28 $There are two inlets A and B connected to a tank. A and B can fill the tank in 32 h and 28 h, respectively. If both the pipes are opened alternately for 1 h, starting with A, then in how much time (in hours, to nearest integer) will the tank be filled?$
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Question 2
20 Jan 2025 Tier II
12 $A tank when full can be emptied by an outlet pipe A in 5.6 hours, while an inlet pipe B can fill the same empty tank in 7 hours. If pipes A and B are turned on alternatively for 1 hour each starting with pipe A when the tank is full, how long will it take to empty the tank?$
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Question 1