Mathematics (Time and Work সময় এবং কার্য)

1) 8 children and 12 men complete a certain piece of work in 9 days, Each child takes twice the time taken
by a man to finish the work. In how many days will 12 men finish the same work ?

2) If 10 men can do a work in 8 days, how many men are needed to complete the work in 5 days?

3) . ‘A' and 'B' together working
with 75% of their efficiencies can complete
a work together in 20 days while 'A' alone
working with his original efficiency takes
48 days to complete the same work. Find
the time taken by 'B' alone (working with
his original efficiency) to complete 55% of
the work.

4) If A can do a piece of work in 4 days, B can do it in 6 days and C can do it in 8 days, how long will it take for A, B and C to complete the work together?

5) A and C working together can complete a task in 24 days. B and C together can do it in 30 days. If A, B, and C together can complete the work in 12 days, how many days will B alone take to finish the work?

6) Pipe A and B can fill the tank in 10 hours and 20 hours respectively where as pipe C can empty the
tank in 8 hours. If all the pipes are opened together at the same time, what is the time to fill the tank
?

7) A man is set to complete a task in 60 days alone. He works for 20 days alone and then a team of 10 helpers joins him, completing the task in another 15 days. How many days would the helpers alone take to finish the entire task?

8) A contractor employed a certain number of workers to complete a project in 40 days. If he had 10 more workers, the project could be completed in 30 days. How many workers did the contractor initially employ?

9) A and B together can
complete 75% of a work in 33 days while
A, B and C together can complete the
whole work in 26 days. If 'C' is 12.5%
more efficient than B then find the time
taken by A and C together to complete
70% of the work.

10) If 24 men can complete a work in 16 days by working 6 hours a day, how many men will be required to complete the same work in 12 days by working 8 hours a day?