$A$ and $B$ together can complete a piece of work in $12$ days and $B$ and $C$ together in $15$ days. If $A$ is twice as good a workman as $C$,then in how many days will $B$ alone complete the same work?

If $10$ men or $20$ boys can make $260$ shirts in $20$ days,then how many shirts will be made by $8$ men and $4$ boys in $20$ days?

$18$ boys can do a piece of work in $24$ days. In how many days can $27$ boys do the same work?

$A$ 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):

$A, B$ and $C$ can do a piece of work individually in $8, 10$ and $15$ days respectively. $A$ and $B$ start working,but $A$ quits after working for $2$ days. After this,$C$ joins $B$ until the completion of the work. In how many days will the work be completed?

$A$ and $B$ together can do a piece of work in $9$ days. If $A$ does thrice the work of $B$ in a given time,the time $A$ alone will take to finish the work is (in days)