$A, B$ and $C$ can do a piece of work in $24, 30$ and $40$ days respectively. They began the work together,but $C$ left $4$ days before the completion of the work. In how many days was the work done?

$P, Q$ and $R$ can finish a work in $10, 12$ and $15$ days respectively. If $Q$ stops after $2$ days,how long would it take $P$ and $R$ to finish the remaining work? (in days)

Raman is $25\%$ more efficient than Aman. If Aman can complete a piece of work in $25$ days,Raman can complete the same work in how many days?

$P$ and $Q$ together can do a job in $6$ days. $Q$ and $R$ can finish the same job in $60/7$ days. $P$ started the work and worked for $3$ days. $Q$ and $R$ continued for $6$ days. Then the difference of days in which $R$ and $P$ can complete the job is

$A$ can do a piece of work in $30 \text{ days}$ while $B$ can do it in $40 \text{ days}$. $A$ and $B$ working together can do it in (in $\text{days}$)

$28$ men can complete a piece of work in $15 \, \text{days}$ and $15$ women can complete the same piece of work in $24 \, \text{days}$. What is the respective ratio between the amount of work done by $30$ men in $1 \, \text{day}$ and the amount of work done by $18$ women in $1 \, \text{day}$?