Three vessels whose capacities are in the ratio of 3:2:1 are completel

Hi Bunuel, could you please share the solutions? Thanks!

You need almost no calculations for this question.

First thing I would note here is that the second and third vessels have the same solution. (ratio of milk : water is 4:1)
Also, since their capacities are 3:2:1, assuming capacities of 3lt, 2 lt and 1 lt, I see that 1 ltr was taken from first vessel (1/3rd), 1 ltr was taken from second vessel (1/2) and 1/7 ltr was taken from third vessel.

So we have 1 ltr of solution with milk:water 5:2 ( which is 28.56% water. Note here that we know 1/7 = 14.28% so 2/7 = 28.56%)
and 1(1/7) ltr of solution with milk:water 4:1 (which is 20% water)

When mixed together, water concentration will be between 20% and 28.56%. Both solutions are taken almost in same quantities with the 20% water solution a little bit extra. So their avg concentration will lie almost in the middle but a tiny bit closer to 20%. Hence, 24% fits perfectly and nothing else does.

Answer (B)

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