Two glasses contain milk and water. In the first glass the

Question

Two glasses contain milk and water. In the first glass the ratio of milk to water is 3 : 2 and in the second glass the ratio of milk and water is reverse of that in first glass. What part of the mixture from first glass should be drawn out and added to the second glass, so that milk and water will be in equal quantities in the second glass?

A. 1/3 
B. 1/4 
C. 2/5
D. 1/2

krisrini · Answer

This was not mentioned in the question. I got this question in one of the paper test. 

I shall wait to see if I get more answers before I post the OA.

SunShine · Answer

I think it should be 1/2.

To have the milk and water ration same one must increase the milk in second glass 1.5 times. if half of the mixture from the first galss (3:2) is added to the second glass it will make the ratio in the second glass as 3:3

Am I right?

Avis · Answer

I think it should be 1/3.

M: W is 3:2

W: M is 2:3

to make the ration W:M the same we need to add some extra milk in the second glass 2+N:3

2+N = 3. => N = 1...but 1 is 1/3 of the the milk portion in the first glass..

I am assuming that the glasses are same size..

giddi77 · Answer

IMHO this question cannot be solved unless the capacitiy of each is specified.

M1:W1 = 3:2
M2:W2 = 2:3

Case 1: Say, they have the same capacity = 50

Then m1 = 30, w1 = 20
& m2 = 20, w2 = 30

Only way to make the solution of equal strength is by adding ALL of milk from Glass1 to Glass2.

Case 2: Gass1 = 100 liters and Glass2 = 50 liters
m1 = 60, w1 = 40
m2 = 20, w2 = 30

We can add HALF od the milk from Glass1 to Glass2 and make the mixtures equal.

If Glass2 doesn't have enough capacity to hold all the milk, JUST DRINK IT :lol:

krisrini · Answer

Giddi, for the first case, I have marked few lines in red, which I think is wrong. 
In your case you assumed the qty to be 50, then as you correctly mentioned the proportions would be 
m1 = 30, w1 = 20 
& m2 = 20, w2 = 30

Which means we need 10 more in Glass2 to make m2=w2, which happens to be 1/3 of m1.

The problem with the questions has correctly pointed out, is not specifying the qty of each glass.
So there are three cases to deal with.

1) Both G1 and G2 are equal. In this case the answer is always 1/3.
2) G1 is greater than G2 then in this case there is no definite answer.
3) If G1 is lesser than G2 then there are few scenarios in which may not get any answer.

So, I would expect such ambiguous question, not come up in my exam day. Just in case they do, I would only assume the quanties in both glasses to be equal.

So with regards to this question, if they are equal the answer is 1/3

giddi77 · Answer

ksrini, Sorry if my comments didn't sound polite. If we add 10 (1/3) from first to second wouldn't that make the M2:W2 = 26 : 34 ? 'coz 10 liters of m1 has 6 liters of milk and 4 liters of water. May be I didn't get the question right. :roll:

Natalya Khimich · Answer

It looks like it should be 1/2 if we assume that initially two glasses contained the same volume of the solution.

ywilfred · Answer

For the case of the 2 glasses having the same capacity (the instance you marked in red), I agree with the working as I have worked it out the same way (albeit with different figures). However, the question says proportion of the mixture in glass1 and not proportion of milk in glass1. The total capacity of the mixture in glass1 is 50 and the proportion should thus be 1/5 (which isn't any one of the given choices). Isn't that right?

Two glasses contain milk and water. In the first glass the

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