$A$ is twice as good a workman as $B$. Working together,they finish a piece of work in $1.5$ days. $A$ alone can finish the work in (in days):

$A$ contract is to be completed in $50 \text{ days}$ and $105 \text{ men}$ were set to work,each working $8 \text{ hours a day}$. After $25 \text{ days}$,$\frac{2}{5}$ of the work is finished. How many additional men must be employed so that the work may be completed on time,with each man now working $9 \text{ hours a day}$?

$A$ and $B$ can complete a work in $15$ days and $10$ days respectively. They started doing the work together,but after $2$ days $B$ had to leave and $A$ alone completed the remaining work. In how many days was the whole work completed?

$P$ is twice as good a workman as $Q,$ and together they finish a work in $16$ days. In how many days can it be done by each separately?

$A$ alone can complete a work in $18 \, days$ and $B$ alone in $15 \, days.$ $B$ alone worked at it for $10 \, days$ and then left the work. In how many more days will $A$ alone complete the remaining work?

$4$ girls can complete a piece of work in $8$ days,the same work $3$ boys can complete in $9$ days,$7$ men in $2$ days,and $5$ women in $4$ days. Who among them has the minimum capacity of work?