Aptitude - Alligation or Mixture - Discussion
Discussion Forum : Alligation or Mixture - General Questions (Q.No. 1)
1.
A vessel is filled with liquid, 3 parts of which are water and 5 parts syrup. How much of the mixture must be drawn off and replaced with water so that the mixture may be half water and half syrup?
Answer: Option
Explanation:
Suppose the vessel initially contains 8 litres of liquid.
Let x litres of this liquid be replaced with water.
| Quantity of water in new mixture = |  |
3 - | 3x | + x |  |
litres |
| 8 |
| Quantity of syrup in new mixture = | |
5 - | 5x | |
litres |
| 8 |
 |
|
3 - | 3x | + x | |
= | |
5 - | 5x | |
| 8 | 8 |
5x + 24 = 40 - 5x
10x = 16
| x = |
8 | . |
| 5 |
| So, part of the mixture replaced = | |
8 | x | 1 | |
= | 1 | . |
| 5 | 8 | 5 |
Discussion:
203 comments Page 2 of 21.
Bikram Tisso said:
4 years ago
Anyone, Please explain in the simplest way to understand.
(19)
Sukumar Natarajan said:
5 years ago
Consider: water is 30 lr and Syrup is 50 lr.
We have to take out 10lr syrup from 50lr. it is clearly 20%.
Note:
It means we are taking out 20 % (= 10 lr) syrup and 20 % (= 6lr) water.
Now we have 40-liter syrup and 24-liter of water remaining. Then we are adding 16-liter water.
Now we have 40-liter syrup and 40-liter water.
We have to take out 10lr syrup from 50lr. it is clearly 20%.
Note:
It means we are taking out 20 % (= 10 lr) syrup and 20 % (= 6lr) water.
Now we have 40-liter syrup and 24-liter of water remaining. Then we are adding 16-liter water.
Now we have 40-liter syrup and 40-liter water.
(17)
Priyanshu Chaudhary said:
2 years ago
If we remove 1 amt of the mixture -> 5/8 amt of syrup is removed.
Let's say our ans is x -> remove x amt of mixture -> (5/8)x or syrup is removed.
for both water and syrup to be in the same amount, the syrup should be 4/8 that is 1/8 of the syrup should be removed from the mixture.
Therefore (5/8)x = 1/8 => x = 1/5 =>ANSWER.
Let's say our ans is x -> remove x amt of mixture -> (5/8)x or syrup is removed.
for both water and syrup to be in the same amount, the syrup should be 4/8 that is 1/8 of the syrup should be removed from the mixture.
Therefore (5/8)x = 1/8 => x = 1/5 =>ANSWER.
(17)
Radhakrishnan said:
5 years ago
Hey, their is a simple way.
Using the left value rule
Left value= intial value * (1- fraction replaced)
We need to find fraction replaced,
Left v = 1/2.
Initial value = 5/8.
Therefore;
1/2 = 5/8 * (1-f).
4/5 = 1-f.
f = 1/5.
Using the left value rule
Left value= intial value * (1- fraction replaced)
We need to find fraction replaced,
Left v = 1/2.
Initial value = 5/8.
Therefore;
1/2 = 5/8 * (1-f).
4/5 = 1-f.
f = 1/5.
(10)
Atr said:
3 years ago
I didn't get this clearly. Please anyone help me.
(10)
Sriman said:
6 years ago
Can anyone please explain how 8/5X1/8 come? Please explain.
(8)
ADITYA PANDITA said:
8 years ago
@All.
The reason in the last step 8/5 is multiplied with 1/8 (or you could say 8/5 is divided by 8) is because we have found x in liters and the answer is required in parts. The 8 that we have used to divide in the last step is not the total 8 parts but it is the 8 liters we have assumed in the beginning of the answer.
The reason in the last step 8/5 is multiplied with 1/8 (or you could say 8/5 is divided by 8) is because we have found x in liters and the answer is required in parts. The 8 that we have used to divide in the last step is not the total 8 parts but it is the 8 liters we have assumed in the beginning of the answer.
(7)
Pujitha said:
2 years ago
@Kamakshi Puri.
The question is about not removing syrup but removing a mixture of the same quantity. So, the water should be added.
The question is about not removing syrup but removing a mixture of the same quantity. So, the water should be added.
(7)
Mrityunjay Yadav said:
7 months ago
At last, we have to find 8/5 litre is how many litres of 8 litres.
So it is 8/5 divide by 8 = 8/5 * 1/8.
So it is 8/5 divide by 8 = 8/5 * 1/8.
(6)
Rajeswari said:
1 month ago
So we practically need to turn a 3:5 ratio into a 1:1 ratio.
3+5 = 8.
8÷2 = 4.
The required ratio is 4:4 to get an equal ratio of liquids.
That means we have to:
3+1 = 4.
5- 1 = 4.
That means we are taking 1 part of 5 and adding it.
it to 3 to get 4:4, which then converts to our required 1:1 ratio.
So, the final answer is 1/5(1 part of 5 is taken out)
Another example: let's say the ratio is 7:11 instead of 3:5.
7+11 =18
18÷2 = 9.
Then the 9:9 ratio is what keeps the mixture 1:1 (half water and half syrup)
To get that, we do :
7 + 2 = 9.
11 - 2 = 9.
That means we take 2 parts of 11 out and add it to 7 parts.
So the answer becomes 2/11 (2 parts of 11 liquid are taken out).
3+5 = 8.
8÷2 = 4.
The required ratio is 4:4 to get an equal ratio of liquids.
That means we have to:
3+1 = 4.
5- 1 = 4.
That means we are taking 1 part of 5 and adding it.
it to 3 to get 4:4, which then converts to our required 1:1 ratio.
So, the final answer is 1/5(1 part of 5 is taken out)
Another example: let's say the ratio is 7:11 instead of 3:5.
7+11 =18
18÷2 = 9.
Then the 9:9 ratio is what keeps the mixture 1:1 (half water and half syrup)
To get that, we do :
7 + 2 = 9.
11 - 2 = 9.
That means we take 2 parts of 11 out and add it to 7 parts.
So the answer becomes 2/11 (2 parts of 11 liquid are taken out).
(6)
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