A contractor estimates that 3 persons could rewire Jasminder's house in 4 days.If,he uses 4 persons instead of three,how long should they take to complete the job?

Two persons could fit new windows in ahouse in 3days.(i) One of the persons fell ill before the work started.How long would the job take now? (ii)How many persons would be needed to fit the windows in one day?

Vinay and Praveen working together can paint the exterior of a house in 6 days. Vinay by himself can complete the job in 5 days less than Praveen. How long will it take Vinay to complete the job.

2 men and 7 boys can do a piece of work in 4 days. It is done by 4 men and 4 boys in 3 days. How long would it take for one man or one boy to do it ?

It takes 12 hours to fill a swimming pool using two pipes. If the pipe of longer diameter is used for 4 hours and the pipe of smaller diameter is used 9 hours, one half of the pool is filled. How long would it take for each pipe to fill the pool separately.

The sum of the ages of A and B is 85 years. 5 years ago, the age of A was twice that of B. Find the present ages. OR A piece of work can be done by 2 men and 7 boys in 4 days. The same piece of work can be done by 4 men and 4 boys in 3 days. How long it would take to do the same work by one man of one boy?

A factor manufactures two types of screws, A and B. Each type of screw requires the use of two machines, an automatic and a hand operated. It takes 4 minutes on the automatic and 6 minutes on hand operated machines to maufacture a package of screw s A, while it take 6 minutes on automatic and 3 minutes on the hand operated machines to maufacture a package of screws B. Each machine is available for at the most 4 hours on any day. The manufacturer can sell a package of screws A at a profit of Rs. 7 and screws B at a profit of Rs 10. Assuming that he can sell all the screw he manufactures, how many packages of each type should the factory owner produced day in order to maximise his profit? Determine the maximum profit.