Question 752567
 how many gallons of 20% antifreeze should be mixed with 10 gallons of 83% antifreeze to obtain 55% antifreeze mixture?
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Equation:
alcohol + alcohol = alcohol
0.20x + 0.83*10 = 0.55(x+10)
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20x + 83*10 = 55x + 55*10
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35x = 28*10
x = (2/7)28
x = 8 gallons (amt. of 20% solution needed)
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Cheers,
Stan H.
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