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Bunuel
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How many litres of water needs to be added to 25 litres of a solution 31 Dec 2019, 03:23
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How many litres of water needs to be added to 25 litres of a solution having milk and water in the ratio 8 : 5, such that the resultant has milk and water in the ratio 5 : 8.

A. 15
B. 20
C. 25
D. 30
E. 40
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A
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How many litres of water needs to be added to 25 litres of a solution 31 Dec 2019, 22:25
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Bunuel
How many litres of water needs to be added to 25 litres of a solution having milk and water in the ratio 8 : 5, such that the resultant has milk and water in the ratio 5 : 8.

A. 15
B. 20
C. 25
D. 30
E. 40

\(\frac{8*25}{ 13(25+x)} =\frac{5}{13}\)
solve for x
40 = 25+x
thus x = 15
thus A
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How many litres of water needs to be added to 25 litres of a solution 31 Dec 2019, 23:50
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Bunuel
How many litres of water needs to be added to 25 litres of a solution having milk and water in the ratio 8 : 5, such that the resultant has milk and water in the ratio 5 : 8.

A. 15
B. 20
C. 25
D. 30
E. 40

Final quantity of water
(8/13)*(25+X)
Initial quantity of water
[(5/13)*25]+X
125+13X=200+8X
X=15
A:)
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How many litres of water needs to be added to 25 litres of a solution 13 Jan 2020, 09:00
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the initial amount of milk=8/13 * 25=200/13 L;
the amount of milk remains the same since water is only added;
therefore, in the final ratio of milk: water =5:8-->5/13 *x=200/13
5x=200;
x=40 Litres; initial amount=25 litres; so, 15 litres of water is added
answer is A)
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How many litres of water needs to be added to 25 litres of a solution 21 Jan 2020, 09:01
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Bunuel
How many litres of water needs to be added to 25 litres of a solution having milk and water in the ratio 8 : 5, such that the resultant has milk and water in the ratio 5 : 8.

A. 15
B. 20
C. 25
D. 30
E. 40

We can create the equation:

8x + 5x = 25

13x = 25

x = 25/13

So originally we have 8 * 25/13 = 200/13 liters of milk and 5 * 25/13 = 125/13 liters of water.

Now we can let w = the number of liters of water added to the solution so that the ratio of milk to water is 5 to 8 and create the equation:

(200/13) / (125/13 + w) = 5/8

5(125/13 + w) = 8(200/13)

625/13 + 5w = 1600/13

5w = 975/13

5w = 75

w = 15

Answer: A
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How many litres of water needs to be added to 25 litres of a solution 21 Jan 2020, 11:48
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=(1-8/13)/(8/13-5/13)
=5/13
So now 5/13=25/x
=> x=15
Can also be done by number line method
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How many litres of water needs to be added to 25 litres of a solution 08 Mar 2025, 17:37
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