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 a house in 3 days : One of the persons fell ill before the work started. How long would the job take now?

Two persons could fit new windows in a house in 3 days : How many persons would be needed to fit the windows in one day?

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

From the pair of linear equations in the following problems and find their solutions (if they exist) by elimination method : 2 men and 5 women can do a piece of work in 4 days. While 4 men and 4 women can finish it in 3 days. How long would it take 1 man to do it ? How long would it take 1 woman to do it ?

500 persons takes 25 days to complete a building.How many persons be needed if the same building has to be completed in 10 days ?

The angle of elevation theta of the top of a light house, as seen by a person on the ground, is such that tan theta=5/2 , When the person moves a distance of 240 m. towards the light house, the angle of elevation becomes phi such that tan theta=3/4 . Find the height of the light house.

A factory 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 manufacture a package of screws A, while it takes 6 minutes on automatic and 3 minutes on the hand operated machines to manufacture 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 screws he manufactures, how many packages of each type should the factory owner produce in a day in order to maximise his profit? Determine the maximum profit