Time and Work Questions

Vikram and Vivek can finish a work in 50 days. They worked together for 20 days and then left. How much work has been done by them?

Pramod can paint a wall red in 12 hours while Brajen can whitewash the wall completely in 16 hrs. If Pramod and Brajen work alternately for an hour each starting when the wall has just cement on it till when it is completely painted red, how many hours will it take to paint the entire wall red?

Anil is twice as good as workman as Bimal and together they finish a piece of work in 9 days. In how many days will Anil alone finish the work?

A painter can paint a fence in 24 hours. After 6 hours he takes a break. What fraction of the fence is yet to be painted?

P and Q can do a project in 12 and 12 days respectively. In how many days can they complete 50% of the project if they work together?

A, B and C can finish a job working alone in 12, 8 and 24 days respectively. In how many days they can finish the job if they worked together?

Ajay can do a painting in 12 days. Amit is 70% more efficient than Ajay. What is the number of days Amit would need to finish the same painting?

A and B can complete a task in 12 days. However, A had to leave a few days before the task was completed and hence it took 16 days in all to complete the task. If A alone could complete the work in 21 days, how many days before the work getting over did A leave?