A is 20% more efficient than B, but he works for five hours a day, whereas B works for 6 hours a day. If both A and B work together, they complete the work in 6 days. How many days are required to complete the work, if only A works for 3 hours a day?

Since A is 20 percent more efficient than B, the ratio of their daily work capacities is 1.2 to 1, or 6 to 5. Working 5 hours a day, A completes 30 units daily, while B working 6 hours daily completes 30 units, meaning their combined daily output is 60 units. They finish the job in 6 days, so the total work is 360 units; if A works alone for 3 hours a day, he completes 18 units daily, and dividing 360 by 18 gives 20 days.

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