Carcass wrote:
The percentage of milk in 100ml. solution X is twice the percentage of milk in 100ml. solution Y. If solution X and solution Y are mixed in the ratio 3 : 2 and 40% of final mixture is milk, what would be the percentage of milk in the solution Y ?
25%
40%
52%
60%
68%
Let the percentage of milk in solution Y be p. Then, in 100ml of solution Y, there are 100 * p/100 = p ml of milk. Since the percentage of milk in solution X is twice that in solution Y, there are 100 * 2p/100 = 2p ml of milk in 100 ml of solution X.
Since solution X and solution Y are mixed in the ratio of 3 : 2, we can assume 300 ml of solution X is mixed with 200 ml of solution Y. There are 3 * 2p = 6p ml of milk in 300 ml of solution X and p * 2 = 2p ml of milk in 200 ml of solution Y. Thus, when the two solutions are mixed, there are 6p + 2p = 8p ml of milk in 300 + 200 = 500 ml of the mixture. We are told that the percentage of the final mixture is 40, thus:
8p/500 = 40/100
8p/5 = 40
8p = 200
p = 25
Therefore, the percentage of milk in solution Y is 25%.
Answer: A