Question

A milkman adds 10 litres of water to 90 litres of milk. After selling $\frac{1}{5}^{	ext{th}}$ of the total quantity, he adds water equal to the quantity he sold. The proportion of water to milk he sells now would be:

Accepted Answer

B. Initially: - Milk = 90 L, Water = 10 L. Total = 100 L. He sells $\frac{1}{5}$ of 100 L = 20 L mixture. - Milk sold = $\frac{1}{5} 	imes 90 = 18$ L - Water sold = $\frac{1}{5} 	imes 10 = 2$ L Remaining mixture: - Milk = $90 - 18 = 72$ L - Water = $10 - 2 = 8$ L He adds 20 L of water: - New Water quantity = $8 + 20 = 28$ L - Milk quantity = 72 L Proportion of water to milk now = 28 : 72.

Milkman ratio of water to milk

Explanation

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