$P$ can complete $\frac{1}{4}$ of a work in $10$ days,$Q$ can complete $40\%$ of the same work in $15$ days,$R$ can complete $\frac{1}{3}$ of the work in $13$ days,and $S$ can complete $\frac{1}{6}$ of the work in $7$ days. Who will be able to complete the work first?

$A$ can do a piece of work in $4\, h$,$B$ and $C$ can do it in $3\, h$,and $A$ and $C$ can do it in $2\, h$. How long will $B$ alone take to do it? (in $h$)

$A$ and $B$ can do a work in $12$ days,$B$ and $C$ in $15$ days,and $C$ and $A$ in $20$ days. If $A, B,$ and $C$ work together,they will complete the work in (in days):

$P$ can do $\left(\frac{1}{4}\right)$ of the work in $10$ days. $Q$ can do $40\%$ of the work in $40$ days and $R$ can do $\left(\frac{1}{3}\right)$ of the work in $13$ days. Who will complete the work first?

Machine $P$ can print one lakh books in $8$ hours,machine $Q$ can print the same number of books in $10$ hours,while machine $R$ can print them in $12$ hours. All the machines are started at $9.00$ a.m. while machine $P$ is closed at $11.00$ a.m. and the remaining two machines complete the work. Approximately at what time will the work be finished?

$A,$ $B,$ and $C$ have to type $506$ pages to finish an assignment. $A$ can type a page in $12$ minutes,$B$ in $15$ minutes,and $C$ in $24$ minutes. If they divide the task into three parts so that all three of them spend an equal amount of time typing,what is the number of pages that $B$ should type?