$10$ men can complete a piece of work in $15$ days and $15$ women can complete the same work in $12$ days. If all the $10$ men and $15$ women work together,in how many days will the work get completed?

$A, B$ and $C$ completed a work costing $Rs. 1800$. $A$ worked for $6$ days,$B$ for $4$ days and $C$ for $9$ days. If their daily wages are in the ratio of $5: 6: 4$,how much amount will be received by $A$ (in $Rs.$)?

Four examiners can examine a certain number of answer papers in $10 \, \text{days}$ by working for $5 \, \text{hours}$ a $\text{day}$. For how many $\text{hours}$ in a $\text{day}$ would $2$ examiners have to work in order to examine twice the number of answer papers in $20 \, \text{days}$? (in $\text{hours}$)

$A$ can finish a work in $18$ days and $B$ can do the same work in $15$ days. $B$ worked for $10$ days and left the job. In how many days can $A$ alone finish the remaining work?

$A$ and $B$ can do a piece of work in $18$ days,$B$ and $C$ in $24$ days,and $A$ and $C$ in $36$ days. In what time can they do it all working together? (in days)

$A$ can do a piece of work in $30$ days while $B$ can do it in $40$ days. In how many days can $A$ and $B$ working together do it?