$A$ group of men decided to do a work in $10 \, days,$ but five of them absented themselves. If the rest of the group finished the work in $12 \, days,$ find the original number of men? (in $men$)

$A$ can do a certain work in $12$ days. $B$ is $60\%$ more efficient than $A$. How many days will $B$ and $A$ together take to do the same job?

Some carpenters promised to do a job in $9$ days,but $5$ of them were absent and the remaining men did the job in $12$ days. The original number of carpenters was:

If $28$ men complete $\frac{7}{8}$ of a piece of work in a week,then the number of men,who must be engaged to get the remaining work completed in another week is

$A$ and $B$ together can do a piece of work in $30$ days. $B$ and $C$ together can do it in $20$ days. $A$ starts the work and works on it for $5$ days,then $B$ takes over and works for $15$ days. Finally,$C$ finishes the work in $18$ days. The number of days in which $C$ alone can do the work is (in days):

Anu can complete a work in $10$ days. Manu is $25\%$ more efficient than Anu,and Sonu is $60\%$ more efficient than Manu. Working together,how long would they take to finish the job? (in days)