If $3$ men or $6$ women can do a piece of work in $16$ days,in how many days can $12$ men and $8$ women do the same piece of work? (in days)

$A$ 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?

If $x$ men can do a piece of work in $x$ days,then the number of days in which $y$ men can do the same work is (in days)

$A$ and $B$ working separately can do a piece of work in $10 \text{ days}$ and $15 \text{ days}$ respectively. If they work on alternate days beginning with $A$,in how many days will the work be completed?

$A$ contractor has the target of completing a work in $40 \text{ days}$. He employed $20$ persons who completed $\frac{1}{4}$ of the work in $10 \text{ days}$ and left. The number of additional persons he has to employ to finish the remaining part of the work as per the target is:

Bindal can finish a work in $10$ days. Jindal is twice as efficient as Bindal. If they work together,in how many days will the work be completed?