X grams of water were added to 80 grams of a strong solution of acid. If as a result, the concentration of acid in the solution became 1/Y times of the initial concentration, what was the concentration of acid in the original solution?
(1) X = 80
(2) Y = 2
What is the best way to determine on which of the 2 statements are the correct answer?
OA E
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Say out of 80 grams, the original solution had p grams of acid, thus, the original concentration of acid = p/80.lheiannie07 wrote:X grams of water were added to 80 grams of a strong solution of acid. If as a result, the concentration of acid in the solution became 1/Y times of the initial concentration, what was the concentration of acid in the original solution?
(1) X = 80
(2) Y = 2
What is the best way to determine on which of the 2 statements are the correct answer?
OA E
After the addition of x grams of water, the new concentration of acid = p/(80 + x)
We are given that
New concentration = 1/y * Original concentration
=> p/(80+x) = p/80y
y = 80/(80+x); 'p' cancels
The above equation suggests that even if we get the values of x and y, we cannot get the value of p/80, thus none of the statements are sufficient.
The correct answer: E
Hope this helps!
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-Jay
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