If 10 gallons of grape juice are added to 40 gallons of a mixture, whi

Question

Tough and Tricky questions: Mixture Problems.

If 10 gallons of grape juice are added to 40 gallons of a mixture, which contains 10 percent grape juice then what percent of the resulting mixture is grape juice?

A. 14%
B. 25%
C. 28%
D. 34%
E. 50%

Kudos for a correct  solution .

PareshGmat · Accepted Answer

Answer = C. 28%

\frac{10 + \frac{10}{100} * 40}{10 + 40} * 100 = \frac{14}{50} * 100 = 28

beattheheat · Answer

Mixture contains 4 gallons of grape juice out of 40 gallons
After addition: 14 gallons of grape juice out of 50 gallons ==> 28% Answer C

g106 · Answer

Amount of Grape juice in the mixture = 10% of 40 gallons = 4 gallons
After Adding 10 more gallons of grape juice total amount of grape juice in the new mixture = 14 gallons out of 50 gallons = 28%

Ans C

qw1981 · Answer

Existing Grape Juice Content= 10% of 40= 4 units
Total Grape huice after adding 10 units= 10+4 =14 units.
Total solution= 40+10=50

GJ %= 100*14/50= 28%.

Answer is C.

Bunuel · Answer

OFFICIAL SOLUTION:

If we start with 40 gallons of a mixture that is 10% grape juice, then we have:

40 × 0.10 = 4 gallons of grape juice.
40 × 0.90 = 36 gallons of other components.

If we add 10 gallons of grape juice, we will end up with 14 gallons of grape juice and 36 gallons of other components, and we will have a total of 50 gallons of the mixture.

So 14/50 of the new mixture is grape juice. Now we convert this to a percent:Percent Grape Juice = 14/50 = 28/100= 28%.

The correct answer is choice (C)

rhine29388 · Answer

40 gallons of mixture which has 10% grape juice means it has 4 gallons grape juice
Total grape juice 10 + 4 = 14 gallons
total mixture = 10 +40 = 50 gallons
concentration = (14/50) * 100 = 28%
therefore resulting mixture has 28 % grape juice
correct answer option C

mathiaskeul · Answer

4 gallons of the 40 gallon mixture is grape juice
we add 10 gallons of grape juice

14 gallons of the 50 gallon mixture is grape juice, multiply by 2 to get the percentage amount.

28% ans c

Abhishek009 · Answer

Grape = 4
Water = 36
Total Juice = 40

After 10 lit grape juice is added

Grape = 4+10 =>14
Water = 36
Total Juice = 40 + 10 =>50

Percent of the resulting mixture as grape juice is (14/50)*100 =>28%

generis · Answer

Using weighted average a little differently ...

Let A = 40 gallons of 10% (= .10) grape juice

Let B = 10 gallons of 100% (= 1) grape juice

(concentration of A)(vol A) + (concen of B)(vol B) = (concen of A + B)(vol of A + B)

.10(40) + (1)(10) =  (\frac{x}{100})  (40 + 10)

4 + 10 =  (\frac{x}{100})  (50)

14 =  \frac{50x}{100}

14 =  \frac{1}{2} x

x = 28

Answer C

JeffTargetTestPrep · Answer

The original mixture contains 0.1 x 40 = 4 gallons of grape juice.

If we add 10 gallons of grape juice into the mixture, we have 14 gallons of grape juice and a total of 10 + 40 = 50 gallons of mixture. Thus, the percentage of grape juice in the mixture is 14/50 = 28/100 = 28%.

Answer: C

gracie · Answer

let x=% grape juice in mixture
.1*40+10=50x
x=14/50=28%
C

ArjunJag1328 · Answer

Mixture = 40 ltrs
Grape juice = 0.10 x 40 = 4 ltrs

After adding 10 ltrs to the mixture.

Total = 50 ltrs
Grape Juice = 14 ltrs (10 + 4)
 
So the question is asking 14 is what percent of 50

14 = x%
50 = 100%

1400 = 50x
x = 1400/50
x = 28%

C is the answer

bumpbot · Answer

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If 10 gallons of grape juice are added to 40 gallons of a mixture, whi

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