$5$ men and $5$ women earn $Rs. 660$ in $3$ days. $10$ men and $20$ women earn $Rs. 3500$ in $5$ days. In how many days can $6$ men and $4$ women earn $Rs. 1060$?

Bindal can finish a work in $10$ days. Jindal is twice as efficient as Bindal. If they work together,in how many days will the work be completed?

$A$ is $30\%$ more efficient than $B.$ How much time will they,working together,take to complete a job which $A$ alone could have done in $23$ days? (in days)

$A$ piece of work can be completed by $10$ men and $6$ women in $18$ days. Men work $9$ hours per day while women work $7.5$ hours per day. The per hour efficiency of a woman is $\frac{2}{3}$ of a man's efficiency. In how many days will $10$ men and $9$ women complete the work?

$A$ is thrice as good a workman as $B$ and therefore is able to finish a job in $60\, days$ less than $B.$ Working together,they can do it in (in $days$)

$A, B$ and $C$ can do a piece of work in $30, 20$ and $10$ days respectively. $A$ is assisted by $B$ on one day and by $C$ on the next day,alternately. How long would the work take to finish? (in days)