A is twice as fast as B and together they can complete a work in 20 days. In how many days can A alone complete the work?

A' takes 6 days less than 'B' to complete a piece of work. If both work together they can complete the same work in 4 days. In how many days will 'B' alone complete the work?

A works 3 times as fast as B. If B can complete a work in 60 days, then in how many days can A and B together complete the same work ?

Mukesh and Dinesh together can complete a work in 120 days. Mukesh alone can complete the work in 150 days. In how many days can Dinesh alone complete the work?

1 man and 1 woman together can complete a piece of work in 8 days. A man alone can complete the work in 10 days. In how many days, can one woman alone complete the work?