A man buys milk at Rs. 5 a litre and mixes it with water.

A man buys milk at Rs. 5 a litre and mixes it with water. By selling the mixture at Rs. 4 a litre he gains 12¹/₂ % on his outlay. How much water did each litre of the mixture contain ?

Here , Gain % = 12	1	% , b = Rs. 5 , a = Rs. 4
	2

According to question , we can say that

Required ratio =	32	= 32 : 13
	13

The quantity of water that the each litre of the mixture contains

=	13	× 1 =	13	litre.
	32 + 13		45