Multiple choice

A can do a piece of work in 4 days and B can do it in 12 days. In how many days will they finish the work, both working together?

  1. 4 days

  2. 6 days

  3. 2 days

  4. 3 days
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Combined rate = 1/4 + 1/12 = 3/12 + 1/12 = 4/12 = 1/3. Time = 1 / (1/3) = 3 days.

AI explanation

A's one day work is 1/4 and B's one day work is 1/12. When working together, their combined one day work is 1/4 + 1/12 = 4/12, which simplifies to 1/3. Using the formula for time taken working together, they will finish the work in the reciprocal of 1/3, resulting in 3 days.

Keep practicing — related questions