<PRE><B>Question 609196</B>
a chemist must mix 6 liters of a 30% acid solution with some of an 80% solution to get a 50% acid solution. How many liters of the 80% solution should be used.

I think I have the equation set up correctly:

0.80x + 0.30*6=0.50(x+5)
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0.8x + 0.30*6 = 0.50*(x + 6) not x+5, you got it right o/w
Solve for x
Multiply by 10 to eliminate fractions
8x + 18 = 5x + 30
x = 4 liters

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