Time and Work on Arithmetic Aptitude related Questions and Answers

Question :   A can do a piece of work in 7 days of 9 hours each, and B can do it in 6 days of 7 hours each. How long will they take to do it, working together 8 2/5 hours a day? 1. 2 2/3 days 2. 2 days 3. 3 1/3 days 4. 3 days Answer :   4 - 3 days