Alligation Or Mixture Ques 18

Question

There was 120 litres of pure milk in a vessel. Some quantity of milk was taken out and replaced with 23 litres of water in such a way that the resultant ratio between the quantities of milk and water in the mixture was $4: 1$ respectively. Again 23 litres of the mixture was taken out and replaced with 27 litres of water. What is the respective ratio of milk and water in the resultant mixture?

(1) $58: 37$

(2) $116: 69$

(3) $69: 43$

(4) $101: 37$

(5) $368: 227$

(BOB Junior Management Grade/Scale-I Exam. 18.04.2015)

Show Answer

Answer: (5)

Solution: (5)

Let $x$ litres of milk was taken out firstly.

$\therefore \frac{120-x}{23}=\frac{4}{1}$

$\Rightarrow 120-x=92$

$\Rightarrow x=120-92=28$ Litres

$\therefore$ Quantity of milk $=120-28=92$ litres

Quantity of water $=23$ litres

Case II

In 23 litres of mixture,

Milk $=\frac{4}{5} \times 23=\frac{92}{5}$ litres

Water $=\frac{23}{5}$ Litres

$\therefore$ Remaining milk $=92-\frac{92}{5}=\frac{460-92}{5}$ $=\frac{368}{5}$ Litres

Quantity of water $=23-\frac{23}{5}+27$ $=\frac{115-23+135}{5}=\frac{227}{5}$ litres

$\therefore$ Required ratio $=\frac{368}{5}: \frac{227}{5}$ $=368: 227$