If $0.6$ times one number is equal to $0.025$ times the other,what is the ratio of the two numbers (in $/24$)?

There is $1000 \, \text{litres}$ of milk in a pot. $100 \, \text{litres}$ of milk is taken out and the same amount of water is poured into it. Again, $200 \, \text{litres}$ of the mixture is taken out and the same amount of water is poured into it, and finally, $400 \, \text{litres}$ of the mixture is taken out and the same amount of water is poured into it. What is the amount of milk in the resulting mixture?

The ratio between Sumit's and Prakash's age at present is $2:3$. Sumit is $6 \text{ yr}$ younger than Prakash. What will be the ratio of Sumit's age to Prakash's age after $6 \text{ yr}$?

₹ $864$ is divided among $A, B$ and $C$ such that $8$ times $A$'s share is equal to $12$ times $B$'s share and also equal to $6$ times $C$'s share. How much (in ₹) did $B$ get?

What must be added to each term of the ratio $2:5$ so that it may equal to $5:6$?

The fourth proportional to $5, 8, 15$ is