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**A dishonest milkman professes to sell his milk at cost price but he mixes it with water and thereby gains 25%. The percentage of water in the mixture is:**

A. 4%
B. 16%
C. 20%
D. 25%
**Answer: Option C**

## Show Answer

Solution(By Apex Team)

Let C.P. of 1 litre milk be Rs. 1
Then, S.P. of 1 litre of mixture = Rs. 1, Gain = 25%
C.P. of 1 litre mixture = Rs. $\left(\frac{100}{125}\times1\right)=\frac{4}{5}$
By the rule of alligation, we have:
∴ Ratio of milk to water = $\Large\frac{4}{5}: \frac{1}{5}$
= 4 : 1
Hence, percentage of water in the mixture = $\left(\frac{1}{5} \times 100\right) \%$
= 20%

## Related Questions On Alligation

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