Aptitude - Alligation or Mixture - Discussion

First, when we took out 4 L of milk, and add 4 L of water, then the mixture become in a ratio of 9:1 then we were going to again checked checking, how much milk is present in the mixture 36 * 9/10 (9+1) = 32.4.

This is the new ratio of milk then we have to do it one more time32.4 * 9/10 = 29.16.

4/40 ratio = 1/10.
Process 2 times so milk ratio 1000:729(1000-729=271water).
40/1000 = 0.04.
0.04 * 729 = 29.16.

I think we can understand this by the formula of successive discounts.

Am I right?

40-litre juice and 0 litre water.

removed 4-litre juices and replace water.
36 litre juice +4 water we get a mixture of 40 litre.
again 4 litre juices remover it means removing mixture,
this 4 litre contain 36liter juice:4 LITER WATER,
36/36+4*4==3.6 litre juices remove.
40==36-3.6=32.2.
4-litre mixture removes we get 32.4:7.6.

32.4/32.4 + 7.6*4==3.24.

32.4-3.24==29.16.

In the first step, 4 litres of milk is taken out from 40 litres it means 4/40=0.1.

It shows that every time 0.1 times the available milk is taken out so in the next step there will be 36 litres of milk. 36 * 0.1=3.6 litres is removed in the second step.

Now, 32.4 litres of milk is remaining in the mixture. Again 32.4 * 0.1=3.24 litres is removed in the third step. Now 29.16 litres of milk is remaining.

@Bhavna

17.7 is the answer for your question, Am I right?

A container has 60 litre of milk 20 litres are drawn out of the container every day and replaced by 20 litre of water what will be the quantity of milk left in the container at the end of the third day? Someone solve this question, please.

Step1: 40 - (10% of 40) = 36.
Step2: 36 - (10% of 36) = 32.4.
Step3: 32.4 - (10% of 32.4) = 29.16.

Here's the ratio of Milk to water at different stages:

Stage 1: 40:0

Stage 2: 36:4 or 9:1

At Stage 3: 4 litres of this mixture was taken out and replaced with water.

In 4 liters of mixture, there are 9 parts milk and 1 part water. So it means that 3.6 litres of milk was removed and 0.4 litres of water was removed.

When we add 4 litres of water, that leaves us with 36 - 3.6 = 32.4 litres of milk and 7.6 litres of water. The ratio of milk to water now is 32.4 : 7.6.

At Stage 4: 4 litres of this mixture was taken out and replaced with 4 litres of water.

4 litres of this mixture will have 0.76 litres of water and 3.24 litres of milk.

So that leaves us with 29.16 litres of milk.

@Parvy Govil.

Very well explained. Thanks.