A can do a job in 10 days and B in 15 days. Working together, how many days will they take?

  1. 5 days
  2. 8 days
  3. 12 days
  4. 6 days
Answer

D) 6 days

In one day they do tfrac110 + tfrac115 = tfrac25150 of the job, so time = tfrac15025 = 6 days.

Quantitative Reasoning MCQ · More Speed, Time, Work & Ages MCQs · Practise