IPMAT Rohtak 2019 (QA) PYQs

An alloy $P$ has copper and zinc in the proportion of $5:2$ (by weight), while another alloy $Q$ has the same metals in the proportion of $3:4$ (by weight). If these two alloys are mixed in the proportion of $a:b$ (by weight), a new alloy $R$ is formed, which has equal contents of copper and zinc. Then, the proportion of copper and zinc in the alloy $S$, formed by mixing the two alloys $P$ and $Q$ in the proportion of $b:a$ (by weight) is

In a bowl containing 60 ml orange juice, 40 ml of water is poured. Thereafter, 100 ml of apple juice is poured to make a fruit punch. Madhu drinks 50 ml of this fruit punch and comments that the proportion of orange juice needs to be higher for better taste. How much orange juice should be poured into the fruit punch that remained, in order to bring up the level of orange juice to 50 percentage?

A merchant made two types of mixed oils P & Q with three different types of oils, X, Y and Z in the ratios 3:2:5 and 4:3:3 respectively with the costs of each litre of X, Y and Z being ₹120, ₹125 and ₹150 respectively. How much profit will the merchant make if he sells 100 litres each of P and Q at the same rate of ₹136 per litre?