How many gallons of water must be mixed with 1 gallon of a 15% salt so

Question

How many gallons of water must be mixed with 1 gallon of a 15% salt solution to obtain a 10% salt solution?

A. 0.50
B. 0.67
C. 1.00
D. 1.50
E. 2.00

ankitranjan · Accepted Answer

you are having 1 gallon of a 15% salt solution means you are having (15/100)*1 gallon of salt.

Now consider you are using x gallons of water and making it to (x+1) gallon of solution.now the salt content(15/100) will be the 10% of total solution.
Hence (10/100)(x+1)=15/100

Solving we get x=0.5 gallon.Answer is A.

Consider KUDOS if it is helpful to u.Thanks.

Bunuel · Answer

Since we are adding pure water then the amount of salt in both solutions will be the same, so 0.15*1=0.1*(1+x) --> x=0.5.

Answer: A.

praneet87 · Answer

Since we are adding pure water

I got the equation

x + .85 = .9 (1 + x)

x - 1/1 of x i.e. only water being added.
.85 - .85 gallons of water 
.9 = the resultant percentage of water + salt.

Solve for it to get .50 Gallons.

gracie · Answer

let w=gallons of water to be mixed
.85+w=.9(1+w)
w=.5 gallons

generis · Answer

Let x = the number of gallons of water to be added

(concentration of A)*(Volume of A) + (concentration of B)* (Volume of B) = (desired concentration in resultant mixture)*(Volume of resultant mixture = A + B)

Water has a salt concentration of 0

(.15)*(1) + (0)(x) = (.10) (1 + x)

.15 = .10 + .10x

.05 = .10 x

\frac{.05}{.10}  = .50

Answer A

profileusername · Answer

How can this be solved by the mixture chart method?

pushpitkc · Answer

Since pure water contains 0% salt
the mixture chart will be as follows :

0(Pure water)  - - - - -  15(Salt Solution) 
- - - - - - - - - - -  10  - - - - - - - - - - - - - 
 5  - - - - - - - - - - - - - - - - - - - - - - -  10

This in in proportion 1 : 2
Since we are mixing 1 gallon of 15% salt solution, which is twice the portion of pure water,
we will be adding 0.5 gallon of pure water(Option A)

Hope this helps

ScottTargetTestPrep · Answer

The initial solution has 0.15 gallons salt. We can let w = the number of gallons of water needed to be added to obtain a 10% salt solution and create the equation:

0.15/(1 + w) = 1/10

1.5 = 1 + w

0.5 = w

Answer: A

ames2020 · Answer

Assume 100 gallons----> salt 15 g : 85 g water
then if you have to add water ---> meaning the salt is going to stay the same amount in the new solution. gives us=
x(10%)=15g
here x is the weight of the new solution
therefore, x=150g
previous was 100 now 150
therefore, 50 gallons of water was added.

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How many gallons of water must be mixed with 1 gallon of a 15% salt so

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