Time and Work Questions

Painter 'A' can paint a house in 10 days and 'B' can do it in 20 days. With help of 'C', they did the job in 5 days only. Then, 'C' alone can do the job in:

A is thrice as productive as C. Together they can complete a job in 22.5 days. If B joins them after they have worked for 15 days then in how many days can they finish the rest of the job if B alone can do the job in 15 days?

S, T and U together can complete a work in 30 days. If the ratio of efficiency of S, T and U is 20 : 15 : 12 respectively, then in how many days U alone can complete the same work?

M is thrice as good as workman as N and together they finish a piece of work in 30 days. In how many days will M alone finish the work?

Prabhat has done 1/2 of a job in 12 days. Santosh completes the rest of the job in 6 days. In how many days can they together do the job?

Parvesh is three times as efficient as Dinesh. Parvesh takes 20 days less than Dinesh to complete a book. If both of them work together, then in how many days the book will be completed?

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?

A labourer can do a job in 50 hours. After 5 hours he takes a break. What fraction of the job is yet to be done?