Ana can finish a filing task in 6 days, and Ben can finish it in 3 days. Working together, how many days will they need?
Correct answer: A. 2 days
Ana does 1/6 of the task per day and Ben 1/3 (= 2/6). Together they do 3/6 = 1/2 per day, so they need 2 days. The combined time is always less than the faster worker's time.
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