CAT (DILR) PYQs

A mixture P is formed by removing a certain amount of coffee from a coffee jar and replacing the same amount with cocoa powder. The same amount is again removed from mixture $P$ and replaced with same amount of cocoa powder to form a new mixture $Q$. If the ratio of coffee and cocoa in the mixture $Q$ is $16: 9$, then the ratio of cocoa in mixture $P$ to that in mixture $Q$ is

Bottle $1$ contains a mixture of milk and water in $7: 2$ ratio and Bottle $2$ contains a mixture of milk and water in $9: 4$ ratio. In what ratio of volumes should the liquids in Bottle $1$ and Bottle $2$ be combined to obtain a mixture of milk and water in $3: 1$ ratio?

A person buys tea of three different qualities at Rs. $800$, Rs. $500$, and Rs. $300$ per kg, respectively, and the amounts bought are in the proportion $2: 3: 5$. She mixes all the tea and sells one-sixth of the mixture at Rs. $700$ per kg. The price, in INR per kg, at which she should sell the remaining tea, to make an overall profit of $50\%$, is