Time and Work Questions

P can do a work in 10 days. Q can do the same work in 15 days. If they work together for 5 days, how much of the work will they complete?

A does 80% of a work in 20 days. He then calls in B and they together finish the remaining work in 4 days. How long B alone would take to do the whole work?

A piece of work was finished by A, B and C together. A and B together finished 60% of the work and B and C together finished 70% of the work. Who among the three is most efficient?

A can do a work in 36 days and B in 12 days. If they work on it together for 3 days, then what fraction of work is left?

A can do a work in 21 days and B in 42 days. If they work on it together for 7 days, then what fraction of work is left?

A carpenter can build a cupboard in 48 hours. After 12 hours he takes a break. What fraction of the cupboard is yet to be built?

Badki can bake 45 cakes in 9 hours, Badki and Chutki together can bake 80 cakes in 10 hours. How many cakes Chutki can bake in 40 hours?

P and Q can do a project in 60 and 30 days respectively. In how many days can they complete 90% of the project if they work together?