A certain number of men do a piece of work in 40 days. If there has been 45 men more, the work could have been finished in 25 days. The original number of men employed at the work were
Some machines complete the work in 4 days. But if 4 other machines are included in this work, then the job shall be completed in 2 days. If capacities of all machines are same, then in how many days 2 machines can complete this work ?