In 24 kg of salt water, 8% is salt; of another mixture, 4% i

Question

In 24 kg of salt water, 8% is salt; of another mixture, 4% is salt. How many kg of 2nd solution must be added to the first mixture to get a solution that is 5% salt?
(A) 24
(B) 36
(C) 48
(D) 72 
(E) None of these

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ShahadatHJ · Accepted Answer

Alligation method:
8--4
--5--
1--3
1 unit of 1 is 24 Kg
Hence, 3 units of equivalent solution = 24*3 = 72 KG

Kartik2121 · Answer

The answer is D

Let us assume the quantity of 2nd mixture to be added is x. Thus, The equation that we can form to make 5% of salt in net mixture is as below:

8% of 24 + 4% of x = 5% of (24+x)

On solving we get x=72 kgs

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twoface07 · Answer

Mixture A : In 24 kg of salt water, we have 0.08*24 = 1.92 kg of salt. Therefore, we have (24 - 1.92) = 22.08 kg of water.

=>   Let's assume we need x kg of salt water to get a mixture of 5% salt.

Mixture B : In x kg of saltwater, we have 0.04x kg of salt and 0.96x kg of water.

Final mixture : When (24+x) kg of salt water is added, we have (1.92+0.04x) kg of salt. The goal is to have a mixture with 5% salt.

=>  \frac{(1.92+0.04x)}{(24+x)}=\frac{5}{100} 
=>   72

The answer is choice (D)

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In 24 kg of salt water, 8% is salt; of another mixture, 4% i

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In 24 kg of salt water, 8% is salt; of another mixture, 4% i

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