CAT (QA) 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

Anil mixes cocoa with sugar in the ratio $3: 2$ to prepare mixture $A$, and coffee with sugar in the ratio $7: 3$ to prepare mixture $B$. He combines mixtures $A$ and $B$ in the ratio $2: 3$ to make a new mixture $C$. If he mixes $C$ with an equal amount of milk to make a drink, then the percentage of sugar in this drink will be

If a certain weight of an alloy of silver and copper is mixed with $3$ kg of pure silver, the resulting alloy will have $90\%$ silver by weight. If the same weight of the initial alloy is mixed with $2$ kg of another alloy which has $90\%$ silver by weight, the resulting alloy will have $84\%$ silver by weight. Then, the weight of the initial alloy, in kg, is