A scientist created a mixture of 3 parts acid and 5 parts ammonia to

Question

A scientist created a mixture of 3 parts acid and 5 parts ammonia to make a 16-ounce solution. If she wants the solution to be 50 percent acid, how much acid should the scientist add?

A. 4 ounces
B. 3 ounces
C. 2 ounces
D. 1 ounce
E. 0.5 ounces

GMATinsight · Accepted Answer

Acid : Ammonia = 3:5

Acid in 16 ounce solution = (3/8)*16 = 6 ounce
Ammonia in 16 ounce solution = (5/8)*16 = 10 ounce

To make a 50% acid solution, Acid = Ammonia as both should be 50% each

hence, extra acid to be added = 10-6 = 4 ounce

Answer: Option A

fmcgee1 · Answer

Ratio of acid to ammonia = 3:5

In fraction form, acid would then be 3/8 of the solution. The question is then asking for the acid to be 50% of the solution, which is 16 ounces.

3/8 = x/16
x=6

So 6/16 is what you currently have.

To make the solution 1:1, you would then:

(6+x)/(16+x) = 1/2
2(6+x) = 1(16+x)
12 + 2x = 16 + x
x = 4

A is the answer.

gracie · Answer

mixture now has 6 ounces of acid
let x=ounces of acid to be added
6+x=(16+x)/2→
x=4 ounces acid
A

satya2029 · Answer

Initial Quantity of acid= 3/8*(16)
=6 ounce
so
6+X=1/2(16+X)
12+2X=16+X
X=4
A:)

Gauriii · Answer

Here is how I did It-
Acid : Amonia
6:10
Now let us add x more ltr of acid
so (6+x)/10 = 1/1 (since new ratio is 1:1)
slove for x, you will get x=4

bumpbot · Answer

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A scientist created a mixture of 3 parts acid and 5 parts ammonia to

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