16 boys or 12 women can do a piece of work in 28 days. In how many days will the same work be done by 4 boys and 4 women, if they all work together?

Two craftsmen, A and B, are paid a total of ₹700 per week by their employer. If A is paid 250% of the sum paid to how much is A paid per week?

 A can do a piece of work alone in 30 days. B is 25% less efficient than A, while C is $$33{1\over 3}$$ % more efficient than B. In how many days can A, B and C, working together, complete the work?

P₁ alone can do $${2\over 3}$$  of the work in 8 days. P₂ alone can do $${7\over 12}$$  of the work in 14 days. P₃ alone can do $${8\over 15}$$   of the work in 16 days. In how many days can they complete the work, if all three work together?

Bobby and Billy can complete a job in 28 days and 20 days, respectively. They work together for 5 days, after which Billy leaves the job. In how many days did Bobby alone complete the rest of the job?

A school has 8 periods of 45 min each, everyday. How long will each period be if the school has to have 9 periods everyday, assuming the working hours to be the same?

 In an office of 900 employees, on a particular day, except for 10% of the female employees, all employees were present. On the next day, except for 8% of the male employees, all employees were present. The number of employees present on each of these two days was the same. Find the total number of male employees on the payrolls of this office.

A and B can together complete a piece of work in 18 days. B and C can together complete the same work in 24 days and A and C can together complete it in 36 days. In how many days can A. B and C, working together, complete this piece of work?