Time, Work, and Projects

Greg completed his homework in 15 minutes. Tom completed it in 1 hour and Dan completed it in half an hour. Who completed the homework in the shortest time duration?

A piece of work, started with 5 working men, takes 20 days to be completed when one man is added per day. Find the same work will be finished in how many days if 12 men work regularly?

x and y, y and z and x and z do a work in 60, 45 and 30 hours, respectively. Then, in how many days can they complete the same work if they work simutaneously and start with x?

If x can do a work in 50 days, y can do the same work in 75 days and z can do it in 100 days. If all work simultaneously and y starts the work, then find out in how many days the work will be finished?

If x and y can do a piece of work in 12 day, y and z can do the same work in 15 days, and x and z can do that work in 20 days, then find the number of days required to finish the work if all (x y z) work simultaneously and the work starts with z.

Three technicians a, b and c have a work to make a server. a and b can make a server in 12 hours, b and c can destroy that server in 15 hour, and c and a can make the server in 20 hours. In how many days will the server be ready to work if a works alone?

Three technicians a, b and c have to make a server. a and b can make a server in 12 hour, b and c can destroy a server in 15 hours, and c and a can make a server in 20 hours. In how many days the server will be ready to work if all of them work together?

Three technicians a, b and c have to make a server. a and b can make a server in 12 hours, b and c can destroy that server in 15 hours, and c and a can make the server in 20 hours. In how many days will the server be ready to work, if the work starts with a and all work simultaneously?

A and B take a tender to do a work worth Rs. 504. If A can work alone for 15 days and B can alone do the same work in 20 days, then find out who gets extra amount and how much extra if both work together.

A maintenance department has supply of commodities for 72 engineers for a period of 54 days. The supply of commodities gets reduced by 10% when 18 more engineers come to work. Find out the number of days for which the engineers will have to work.

A, B and C take a tender to make a wall with Rs. 6072. If all work alone simultaneously, they complete the work in 15, 20 and 12 days, respectively. But, they work together to complete the wall. Find the highest amount accepted and the person who gets it.

A man starts a work and one more man is added from the 2^nd day regularly. If the work is finished in 30 days, then find how many days would be required to complete the same work with 1 man working regularly?

x can make a wall in 25 months, y can make the same wall in 35 months and z can break that wall in 45 months. How many months will it take for them to completely construct the wall once when all three of them work together?

Worker A takes 8 hours to do a job. Worker B takes 10 hours to do the same job. How long should it take both A & B, working together but independently, to do the same job?