Question

Two vessels $A$ and $B$ contain milk and water in the ratio of $5:2$ and $2:3$. When these mixtures are mixed to form a new mixture containing half milk and half water, they must be taken in the ratio :

• A. $2:5$
• B. $7:3$
• C. $1:2$
• D. $4:5$
• E. $7:15$
• F. None of these

Answer 1

Answer: (E)

$7:15$

We have,

Milk in vessel A = 5/7,

Water in vessel A = 2/7,

Milk in vessel B = 2/5 and

Water in vessel B = 3/5.

Let x litres of mixture in A is mixed with y litres of mixture in B.

$\frac{5x}{7}+\frac{2y}{5}=\frac{2x}{7}+\frac{3y}{5}$

or, $\frac{3x}{7}=\frac{y}{5}$

or, x/y = 7/15.

Hence, (E) is the correct answer.