CAT (QA) PYQs

A trader sells $10$ litres of a mixture of paints $A$ and $B$, where the amount of $B$ in the mixture does not exceed that of $A$. The cost of paint A per litre is Rs. $8$ more than that of paint B. If the trader sells the entire mixture for Rs. $264$ and makes a profit of $10 \%$, then the highest possible cost of paint B, in Rs. per litre, is

A container holds 200 litres of a solution of acid and water, having 30% acid by volume. Atul replaces 20% of this solution with water, then replaces 10% of the resulting solution with acid, and finally replaces 15% of the solution thus obtained, with water. The percentage of acid by volume in the final solution obtained after these three replacements, is nearest to

The strength of a salt solution is $p\%$ if $100 \mathrm{ml}$ of the solution contains p grams of salt. If three salt solutions $A, B, C$ are mixed in the proportion $1: 2: 3$, then the resulting solution has strength $20 \%$. If instead the proportion is $3: 2: 1$, then the resulting solution has strength $30 \%$. A fourth solution, $D$, is produced by mixing $B$ and $C$ in the ratio $2: 7$. The ratio of the strength of $D$ to that of $A$ is