Two solutions S1 and S2 contain whisky and soda in the ratio 2 : 5 and 6 : 7 respectively. In what ratio these solutions be mixed to get a new solution S3, containing whisky and soda in the ratio 5 : 8 ?
Answer: A
Let the amount taken from S1 be 7x
And amount taken from S2 be 13y
(2x + 6y)/(5x + 7y) = 5/8
16x + 48y = 25x + 35y
9x = 13y
x/y = 13/9
Actual ratios of amounts
= 7x/13y
= (7/13) * (13/9)
= 7/9