40 men can complete a work in 48 days. 56 men started for the same work for x days. After x days, 16 men increased, so, the remaining work is completed in $13\frac{1}{3}$ days. Find x?

Neha can complete a work in 6 days and Ishrat can complete the same work in 4 days. What will be the time taken by them to complete the same work together ?

A and B can complete a job in 24 days working together. A alone can complete it in 32 days. Both of them worked together for 8 days and then A left. The number of days B will take to complete the remaining job is:

A and B can do a piece of work in 12 days; B and C together can do it in 15 days. If A is twice as good a workman as C, find the number of days in which B alone can do the work?

A and B working together can finish a piece of work in 12 days while B alone can finish the same work in 30 days. Then determine that in how many days can A alone finish the same work?

X, Y and Z together can do a piece of work in 16 (4/11) days. X and Y together can do the same work in 20 days. In how many days will Z alone finish the 60% of the work?

30 boys are engaged to do a piece of work in 15 days but it is found that in 5 days, 3/5 work is completed. How many boys may be allowed to go off, so that the work may be finished on time?