Aptitude - Ratio and Proportion - Discussion

We can solve this simply
part of water is 1/3 in 60ltr
so 60*1/3=30
1 part is 30 then 2 part of same 60ltr is 60 ltr.

A mixture contains milk and water in the ratio 5:1. On adding 5 litres of water, the ratio of milk to water becomes 5:2. The quantity of mil in the original mixture is

A) 16 litres B) 25 litres C) 22.75 litres D) 32.5 litres

Hey can anyone explain this for me ?

@Sai

5x/(1x+5)=5/2
10x=5x+25
5x=25

I think 25 litres is the correct ans what do u say guys ?

Let the ratio be 2x and 1x
add it to get,
2x+1x=60
3x=60
x=20
now,milk=2x20=40ltr.
and water=1x20=20ltr.
we know that something is added to water..
therefore,new ratio is 1:2 after adding the quantity of water
therefore,40/20+x=1/2 ( note that x=new quantity of water that is to be added)
cross multiply it and u will get the ans. =60
Hence proved.

Good Kartik Negi your ans is right and simple..

With the help of first ratio 2:1 we find already milk 40 liters and 20 liters water (total 60 liter of mixture). But I don't why we taken 40 liters of milk is consider as 1 part for the new ratio (1:2). Actually in old ratio 40 liter is 2 part. Please any one clarify please.

Thank you karthik negi for your clear and crisp explanation.

@Bagavathi.

In 60lts of mixture the ratio of milk and water is 2:1. It means 40lts of milk and 20 lts of water. In the question he just asked only how much of water is added to make the ratio of milk dan water to 1:2.

So the quantity of milk is unchanged i.e, 40lts. and the quantity of water required is 60lts. Now the total quantity of mixture is 120 lts in which 40lts of milk is 1part. In the old ratio the total mixture is 60lts so 40 lts of milk is 2part.

The original ratio is 2:1.

That means 40 liters milk and 20 liters water.

We have to add x liters of water so that ratio becomes 1:2.

Here milk quantity doesn't change.

So in 1:2 ratio.

1 part is equal to 40liters.

2 parts-------------------?

80liters.

So the quantity of water to be added is 80-20=60.

Ramesh Nicely explained .....