Aditya and Manish continued in a joint business for $36$ months. Aditya contributed $Rs. 300$ for a certain time and Manish invested $Rs. 500$ for the remaining time. If out of a total profit of $Rs. 1020$,Aditya gets $Rs. 495$,then for how many months did Aditya keep his money?

$A$ dishonest trader professes to sell his article at cost price but he uses $900 \, g$ weight instead of $1 \, kg$. What is the percentage gain of the trader in this trade?

Acid and water are mixed in a vessel $A$ in the ratio of $5:2$ and in the vessel $B$ in the ratio $8:5$. In what proportion should quantities be taken out from the two vessels so as to form a mixture in which the acid and water will be in the ratio of $9:4$?

Milk and water in a mixture are in the ratio $7:5$. When $15 \, L$ of water is added to it,the ratio of milk and water in the new mixture becomes $7:8$. The total quantity of water in the new mixture is........$L$

$A$ person travels $285 \text{ km}$ in $6 \text{ hours}$ in two stages. In the first part of the journey,he travels by bus at a speed of $40 \text{ km/h}$. In the second part of the journey,he travels by train at a speed of $55 \text{ km/h}$. How much distance did he travel by train? (in $\text{km}$)

The ratio of milk and water in mixtures of four containers are $5:3, 2:1, 3:2$ and $7:4$ respectively. In which container is the quantity of milk,relative to water,minimum?