If $10$ men can do a piece of work in $12$ days,the time taken by $12$ men to do the same piece of work will be (in days).

If $8$ men or $10$ women can do a piece of work in $50$ days,in what time will $28$ men and $15$ women do it? (in days)

$A$ is $50\%$ as efficient as $B$. $C$ does half of the work done by $A$ and $B$ together in the same time. If $C$ alone does the work in $20 \text{ days}$,then $A, B$,and $C$ together can do the work in (in $\text{days}$):

$A$ and $B$ together can complete a work in $10$ days. They started together,but $A$ left after $2$ days and the remaining work was completed by $B$ in $12$ days. In how many days can $A$ complete the entire work while working alone?

$2$ men and $1$ woman can do a piece of work in $14$ days,while $4$ women and $2$ men can do the same work in $8$ days. If a man gets $Rs. 90$ per day,what should be the wages per day of a woman? (in $Rs.$)

$4$ men or $6$ women or $10$ children can paint a house in $5$ days. The painting is given to a couple (a man and a woman) and their $5$ sons. They finish the job in (in days):