# How many Litres of water must be added to 75 Litres of milk that contains 13% water to make it 25% water in it?

#### Explanation:

In the mixture of 45 litre,

 Milk= 45 × 4 = 36ltr, Water= 45 × 1 = 9ltr 5 5
New ratio, = 9 + 3 : 36 + 4 = 12 : 40 = 3 : 10

Hence, option B is correct.

#### Explanation:

Total mixture = 48 + 144 = 192 litre

% of Glycerin = 48/ 192 × 100 = 25% = % of Rose water = 75%

In the final mixture glycerin= 30%, Rose water = 70%

(48 – D × 25% + 32) : (144 – D × 75% + 48) = 3 : 7

7 (48 – D × 25% + 32) = 3 (144 – D × 75% + 48)

7 (80 – 0.25 D) = 3 (192 – 0.75 D)

560 – 1.75 D = 576 – 2.25 D

2.25 D – 1.75 D = 576 – 560

Hence, option B is correct.

#### Explanation:

Let alchohol = 6x, water = 5x According to the question,

 6x – 22 × 6 : 5x – 22 × 5 + 22 = 9 : 13 11 11
6x – 12 : 5x – 10 + 22 = 9 : 13 13 (6x – 12) = 9 (5x + 12) 78x – 156 = 45x + 108 78x – 45x = 156 + 108 33x = 264 x = 8 Water after replacement = 5 × 8 – 10 + 22 = 40 + 22 = 52 litre

Hence, option D is correct.

#### Explanation:

Let required amount of second solution to be added = a L

 Then 15 × 20 + 5a = 10 20 + a
⇒ 300 + 5a = 200 + 10a ⇒ 5a = 100 ⇒ a = 20

Hence, option (D) is correct.

#### Explanation:

Given, quantity of the alloy = 200 gm.

If Copper : Zinc = 2 : 3

 Then quantity of Copper = 2 × 200 = 80gm 5

 And quantity of Zinc = 3 × 200 = 120gm 5
As per the  question,
⇒ x = 100 gm So  The quantity of Copper to be added is 100gm

Hence, option B is correct.

#### Explanation:

Let the quantity of  Rs.5.4 per kg rice = x kg

According to the question,

x × 5.4 + 4.5 × 10 = 5.94 × (10 + x) ÷ 120 × 100

5.4x + 45 = 4.95 × (10 + x)

Hence, option A is correct.

#### Explanation:

Let, Ducks = x, Rabbit = y

As, Duck has 2 legs and rabbit has 4 legs,

Hence, option A is correct.

#### Explanation:

Let the capacity of each be ‘a’ litre Then quantity of milk in container after mixing is

 = ( 3 × 6 + 7 × 3 + 11 × 2 ) a 30

And  quantity of water in container after mixing is
⇒ required  ratio of milk to water after mixing
 = = 61:29
Hence option C is correct.

#### Explanation:

Let the required volume of water to be added = x ml

When added to 7 ml lotion, the total volume = “7 + x” ml

If the lotion contains 70% alcohol, then it contains 30% water

If it contains 35% alcohol, it contains 65% water.

By balancing the volume of water before and after dilution of the lotion, we get :

(Amount of water in lotion before dilution) + (amount of water added) = (amount of water in lotion after dilution)

(30% of 7) + x = (65% of “7 + x”)

( 30 × 7 ) + x = 65 × 7 + x

⇒ 210 + 100x = 65 × (7 + x)

Hence, option (C) is correct.

#### Explanation:

The quantity of milk in the mixture

The quantity of water in the mixture

= 35 – 20 = 15 litres

Now, let the quantity of water added to the mixture be x litres. Then water becomes 60% of the total quantity of mixture. ∴   Required % of water in mixture

 = Total quantity of water = 60% Total quantity of mixture

⇒  75 + 5x = 105 + 3x ⇒  2x = 30

∴  x = 15 litres.

Hence, option D is correct.

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How many litres of water needs to be added to 25 litres of a solution [#permalink]

31 Dec 2019, 02:23

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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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Re: How many litres of water needs to be added to 25 litres of a solution [#permalink]

31 Dec 2019, 21:25

Bunuel wrote:

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+xthus x = 15thus A _________________

Keep it simple. Keep it blank

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Re: How many litres of water needs to be added to 25 litres of a solution [#permalink]

31 Dec 2019, 22:50

Bunuel wrote:

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]+X125+13X=200+8XX=15

A:)

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Re: How many litres of water needs to be added to 25 litres of a solution [#permalink]

13 Jan 2020, 08:00

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=200/135x=200;x=40 Litres; initial amount=25 litres; so, 15 litres of water is added

answer is A)

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Re: How many litres of water needs to be added to 25 litres of a solution [#permalink]

21 Jan 2020, 08:01

Bunuel wrote:

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 = 2513x = 25x = 25/13So 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) = 5/85(125/13 + w) = 8(200/13)625/13 + 5w = 1600/135w = 975/135w = 75w = 15

Answer: A

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How many litres of water needs to be added to 25 litres of a solution [#permalink]

21 Jan 2020, 10:48

=(1-8/13)/(8/13-5/13)=5/13So now 5/13=25/x=> x=15Can also be done by number line method

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Re: How many litres of water needs to be added to 25 litres of a solution [#permalink]

28 Apr 2022, 08:00

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Re: How many litres of water needs to be added to 25 litres of a solution [#permalink]