Question

A vendor wants to gain 25% by adding water to milk and selling the mixture at the cost price. Find the ratio of water and milk in the mixture.

• A. 2 : 5
• B. 1 : 4
• C. 2 : 7
• D. 1 : 5

Answer 1

Answer:

B. 1 : 4

Let the cost price of milk = ₹1 per unit.

Let water be free (cost = 0), and mixture is sold at cost price with 25% gain.

Selling condition

He sells mixture at CP but gains 25%, so:

$\text{Selling Price} = 125\% \text{ of CP}$

So,
$\text{CP of mixture} = \frac{100}{125} = \frac{4}{5}$

This means:

• 1 unit mixture costs him ₹0.8

So milk portion must be 0.8 of mixture, rest is water.

Water and milk ratio

Milk in 1 unit mixture = 0.8
Water = 0.2

$\text{Milk : Water} = 0.8 : 0.2 = 4 : 1$

So reverse for water : milk:

$\text{Water : Milk} = 1 : 4$
Final Answer:

Water : Milk = 1 : 4