SOLUTION: How many liters of 10% acid solution must be added to a 40% acid solution to produce an 8 liters volume 30% acid solution

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Question 1154192: How many liters of 10% acid solution must be added to a 40% acid solution to produce an 8 liters volume 30% acid solution
Found 3 solutions by josmiceli, josgarithmetic, greenestamps:
Answer by josmiceli(19441)   (Show Source):
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Let = liters of 10% acid solution needed
= liters of 40% acid solution needed
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liters of 10% solution are needed
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check:

OK

Answer by josgarithmetic(39618)   (Show Source):
You can put this solution on YOUR website!
Two-part mixture can generally be solved as:
How many liters of L% solution be added to H% solution to produce M liters of T% solution?

v, volume of the H% solution
M-v volume of the L% solution

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Substitute your given , and evaluate v.

Answer by greenestamps(13200)   (Show Source):
You can put this solution on YOUR website!

Here is a quick and easy way (if you understand it!) to solve two-part mixture problems like this.

(1) 30% is "twice as close" to 40% as it is to 10%. (The difference between 40 and 30 is half the difference between 30 and 10.)

(2) That means the mixture needs to use twice as much of the 40% acid as the 10% acid.

(3) Twice as much means 2/3 of the mixture needs to be the 40% acid, so 1/3 is the 10% acid.

ANSWER: 2/3 of 8 liters, or 16/3 liters, of 40% acid; 1/3 of 8 liters, or 8/3 liters, of 10% acid.