Time and Work Questions

A and B can together do a piece of work in 6 days and A alone can do it in 9 days. The number of days B will take to do it alone is

A can do a piece of work in 8 days and B can do it in 10 days seperately. How many days would it take for both A and B to finish the same work together?

X alone can do a piece of work in 12 days and Y alone can do the same work in 6 days. In how many days will both together complete the same work?

A can complete a work in 20 days and B can complete the same work in 25 days. If both of them work together, then in 3 days what percent of the total work will be completed?

A can do a work in 20 days and B in 10 days. If they work on it together for 5 days, then what fraction of work is left.

Working 10 hours a day, Aman can complete a piece of work in 18 days. How many hours a day should he work so as to finish the work in 15 days?

A and B together do a job in 15 days and A alone could do the same job in 20 days. How many days would B take to do half the job if he worked alone?

A, B and C can do a job working alone in 12, 16 and 24 days respectively. In how many days they can do the job if they worked together?