Multiple choice

A can do a piece of work in 20 days and B can do the same work in 60 days. If both do the work together, in how many days will they complete the work?

  1. 12 days

  2. 15 days

  3. 16 days

  4. 18 days

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A's rate = 1/20, B's rate = 1/60. Combined rate = 1/20 + 1/60 = 3/60 + 1/60 = 4/60 = 1/15. Time taken = 15 days.

AI explanation

Using the Time and Work formula for combined work, the time taken equals the product of their individual times divided by the sum of their times. The calculation is (20 * 60) / (20 + 60), which equals 1200 / 80. This gives a result of 15 days.

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