$8$ children and $12$ men complete a certain piece of work in $9$ days. If 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?

$A$ and $B$ can complete a piece of work in $15$ days and $10$ days respectively. They contracted to complete the work for $Rs. 30000$. The share of $A$ in the contracted money will be (in $Rs.$)

$A$ and $B$ can do a piece of work in $45$ days and $40$ days respectively. They began to do the work together,but $A$ leaves after some days and then $B$ completed the remaining work in $23$ days. The number of days after which $A$ left the work was:

$A$ worker can complete a piece of work in $50$ days. On the first day,he works alone. On the second day,one more person joins him,on the third day,one more person joins them,and this process continues until the work is completed. How many days are needed to complete the work?

$A$ and $B$ can do a piece of work in $12$ days and $15$ days,respectively. They began to work together,but $A$ left after $4$ days. In how many more days would $B$ alone complete the remaining work?

$4$ men or $6$ women can finish a piece of work in $20$ days. In how many days can $6$ men and $11$ women finish the same work?