In what ratio must $25 \%$ hydrochloric acid be mixed with $60 \%$ hydrochloric acid to get a mixture of $40 \%$ hydrochloric acid?

In what ratio should tea at ₹ $240$ per $kg$ be mixed with tea at ₹ $280$ per $kg$ so that on selling the mixture at ₹ $324$ per $kg$ there is a profit of $20 \%$?

$A$ trader has $50 \ kg$ of sugar,a part of which he sells at $10 \%$ profit and the rest at $5 \%$ loss. He gains $7 \%$ on the whole. What is the quantity sold at $10 \%$ gain and $5 \%$ loss? (in $kg$)

The cost of Type $1$ rice is ₹ $15/kg$ and Type $2$ rice is ₹ $20/kg$. If both Type $1$ and Type $2$ are mixed in the ratio of $2:3$,then the price per $kg$ of the mixed variety of rice is (in ₹):

In what ratio must water be mixed with milk to gain $16 \%$ on selling the mixture at cost price?

In what ratio must a grocer mix two varieties of tea worth ₹ $60$ a $kg$ and ₹ $65$ a $kg$ so that by selling the mixture at ₹ $68.20$ a $kg$ he may gain $10 \%$?