Multiple choice

A can do a piece of work in 20 days and B can do the same piece of work in 30 days. Find in how many days both can do the work?

  1. 28

  2. 20

  3. 34

  4. 12

  5. 10
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Combined rate = 1/20 + 1/30 = 3/60 + 2/60 = 5/60 = 1/12. Time = 12 days.

AI explanation

Assume the total work is the least common multiple of 20 and 30, which is 60 units. A completes 3 units per day and B completes 2 units per day, giving a combined capacity of 5 units per day. The total time taken is 60 units divided by 5 units per day, resulting in 12 days.

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