Time and Work

A can complete a project in 2 months, B can complete the same in 1 month and C can complete it in 20 days. All of them started working together. After five days, A left the project. How many more days are needed to complete the project?

A piece of work is to be done in a school which 16 men or 20 women can finish in 25 days. How many days will 28 men and 15 women take to finish this job?

12 men and 5 women can complete a piece of work in 2 days, whereas 4 men and 3 women can complete the same piece of work in 5 days. In how many days can 8 men complete the piece of work?

Three girls A, B and C can do a certain piece of work in 12, 36 and 48 days, respectively. All of them started working together and then B left after working for 2 days. After that A and C worked together for 3 days and then A left. In how many days was the remaining work done by C?

A contractor undertakes to complete a job in 60 days and employs 90 persons for the same. After 45 days, when he takes a review, he finds that 90% of the work is over. In order to finish the work in 60 days, how many persons should he now remove from this job?

A can do 1/5 of a job in 10 days and B can do 1/3 of the job in 25 days. In how many days can they do half of the job working together?

Working 8 hours a day, 12 men can complete a task in 16 days. If the same task must be completed in 8 days only, then how many more people would be required if all of them work for 12 hours a day?

Working alone, A can do a piece of work in 72 days and B in 90 days. If they work on it together for 10 days, then what fraction of work will be left?

A takes 50% more time than B who can complete a piece of work in 20 days. Both A and B started working together. After 6 days, A left the work and B did half of the pending work alone. Then, A joined B and they completed rest of the work together. In how many days was the whole work completed?

A and B can finish a piece of work in 16 days, while A alone can do the same work in 24 days. In how many days can B alone complete the work?

A and B, each working alone, can do a work in 15 days and 25 days, respectively. They start the work together, but B leaves after some time and A finishes the remaining work in 7 days. How many days after the start of work does B leave?

A can complete a work in 20 days and B can do the same in 30 days. A works alone for 4 days and then B completes the remaining work along with C in 18 days. In how many day can C complete the work alone?

A man is twice as efficient as a woman and a woman is twice as efficient as a boy in doing a work. If all of them can finish the work in 7 days, then in how many days will the boy finish the work alone?

15 men take 20 days to complete a job, working 8 hours a day. How many hours a day should 20 men work to complete the job in 12 days?