CAT Practice : Averages, Ratios, Mixtures

When we mix two mixtures in a particular ratio, we get a third mixture. Given the third mixture how does one find the ratio in which they were mixed.


    Q.26: 3L of milk are drawn from a container containing 30L of milk. It is replaced by water and the process is repeated 2 times. What is the ratio of milk to water at the end?


  • Correct Answer
    Choice C.

Detailed Solution

Formulae (derived using allegation):
Milk left = Capacity x (1 – fraction of milk withdrawn)n
Therefore, milk left = 30 x 0.93
= )
= )
So, Water in container = 30 –
= )
Therefore, Milk : Water = 2187 : 813 = 729 : 271

Correct Answer:

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