Question

A vessel contains certain volume of milk and water mixed in the ratio 7 : 3. A part of this mixture is removed and replaced by an equal quantity of pure milk. Now the ratio of milk and water in the vessel is found to be 17 : 2. What proportion of the original volume has been replaced by pure milk?

Answer 1

milk=7
water=3
changeinmilk=addedliquid-addedliquid*7/10
changeinwater=-addedliquid*3/10
(milk+changeinmilk)/(water+changeinwater)=17/2

Answer 2

(7+.3x)/(3-.3x)=17/2

Answer 3

8.222

Answer 4

how added liquid in milk two time no removal of milk

Answer 5

something went wrong here

Answer 6

let T be the total volume, then (7/10)T is milk. Let x be the about that is replaced by pure milk. Then the new amount of milk is
(7/10)(T-x) + x, which is 17/19 of the total.

so,
(7/10)(T-x) + x = (17/19)T
x = (37/57)T

about 64.91% of the total volume