Question

Two vessels a and b contain alcohol and water in the ratio 7 : 5 and 17 : 7 respectively. In what ratio should the mixtures from two vessels a and b be mixed to get a new mixture containing alcohol and water in the ratio 5 : 3?

Answer 1

let x part of 1st vessel combine with y part of 2nd vessel.
7x+ 17y of alcohol combine with 5x+7y water
now (7x+17y)/(5x+7y) = 5/3
21x+51y=25x+35y
4y=1x
then x/y=4/1
so ratio is 4:1