A 48 gallon solution of salt and water is 10% salt. How many gallons

Question

A 48 gallon solution of salt and water is 10% salt. How many gallons of water must be added to the solution in order to decrease the salt to 8% of the volume?

A. 8
B. 12
C. 13
D. 14
E. 16

OptimusPrepJanielle · Accepted Answer

Amount of salt = 4.8
Assume x gallons of water are added.

4.8 / 48 + x = 8/100
480 = 8x + 384
8x = 96
x = 12

Correct Option: B

mohshu · Answer

Amount of salt = 10% of 48 = 4.8 gallons

this 4.8 gallons will be 8% of new mixture 
therefore, 
resulting mixture = 4.8/0.08 = 60 gallons

gallons to be added = 60-48 = 12 gallons,, option B

snorkeler · Answer

N1*V1=N2*V2

10*48 = 8*V2

V2=60 --> 60-48 = 12

gracie · Answer

let x=gallons of water to be added
.9(48)+x=.92(48+x)
x=12 gallons

Abhishek009 · Answer

Capture.PNG Now we get 8% = 4.8 So, 100% = 4.8/8*100 Hence , 100% = 60 We know 48 + x = 60 So, X = 12 Hence answer must be (B) 12

msk0657 · Answer

Let the quantity of water to be added be X liters.

Quantity of Salt in the gallon = 10/100 ( 48) = 4.8 liters.

=> 4.8 = 0.08 ( 48 + X ) ( Here the quantity remains same but the concentration gets diluted, since we add X liters of water.
=> 48 = 8/10 ( 48 + X ) 
=> 480 = 384 + 8X
=> 96 = 8X
=> X =12. ---> Choice B.

sasyaharry · Answer

Backsolve. I started with B because it was easy.
48+12=60.
8% of 60=4.8

Answer is  B

generis · Answer

Let x = amount of water to be added.

Water is 0% salt. It is added in on LHS to track on the idea that two quantities are being mixed (the 10% solution and water)**

(.10)(48) + 0x = (.08)(48 + x)

4.8 + 0x = 3.84 + .08x

.96 = .08x ---> 96 = 8x

x = 12

Answer B

**Method
Let 48 gallon solution = A
Let water to be added = B

A + B = Total volume of resultant solution

(A's Concentration)(A's Volume) + (B's Concentration)(B's Volume) = (Desired Concentration)(Total Volume of resultant solution)

AkshdeepS · Answer

can we use this formula in the below question https://gmatclub.com/forum/how-many-lit ... ml#p903692

ScottTargetTestPrep · Answer

Currently we have 0.1 x 48 = 4.8 gallons of salt. We can let the amount of water added = y; thus:

4.8/(48 + y) = 8/100

4.8(100) = 8(48 + y)

480 = 384 + 8y

96 = 8y

12 = y

Alternate Solution:

We have 48 gallons of a 10% solution. We will add x gallons of water (0% solution), which will yield (48 + x) gallons of an 8% solution. Putting this into an equation, we have:

48(0.10) + x(0.0) = (48 + x)(0.08)

4.8 = 0 = 3.84 + 0.08x

0.96 = 0.08x

96 = 8x

x = 12

Answer: B

harshbirsingh · Answer

10% of 48 = 4.8 gallons of salt

4.8*100/(48+x)=8

Therefore, x=12

Answer is Option B

MathRevolution · Answer

The 48-gallon solution of salt and water is 10% salt.

=> 4.8 is salt and 43.2 is water

Water is to be added so that salt in the new solution is 8%.

=>  \frac{{4.8} }{ {48 + w}}  =  \frac{8}{100 }

=> 480 = 8x + 384

=> 8x = 96

=> x = 12

Answer B

e3thekid · Answer

Salt = 10% of 48 gallons 
Salt = 4.8

To get the percentage of salt down to 8%, we must add x gallons of water to total amount.

We can set this up with the following equation: 
Salt / Salt and water + amount of water = salt % 
(Let’s assign the variable x to find the amount of added water needed.)

4.8/48 + x = 8/100

We can cross multiply to find x.

480 = (8)(48) + 8x (divide both sides by 8)
60 = 48 + x 
12 = x

12 gallons of added water are needed to get the concentration of salt to decrease to 8%

Option B

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A 48 gallon solution of salt and water is 10% salt. How many gallons

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