Question 433610
 how many gallons of a 25% acid solution must be mixed with 100 gallons of a 6% acid solution to obtain a mixture that is 20% acid?
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Equations:
acid + acid = acid
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0.25x + 0.06*100 = 0.20(x+100)
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Multiply thru by 100 to get:
25x + 6*100 = 20x+20*100
5x = 14*100
x = 14*20
x = 280 gallons (amt of 25% solution needed)
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Cheers,
Stan H.