<PRE><B>Question 65087</B>
How much pure antifreeze should be added to 300 gallons of 30 percent antifreeze solution to raise the antifreeze solution to 40 percent?
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Amt of 100% afreeze = x gallons ; amt of active ingrediant=1.00x gallons
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Amt of 30% afreeze = 300 gallons; amt of active ingrediant=0.30(300)=90 gals
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Amt of 40$ afreeze = x+300; amt of active ingrediant = 0.4(x+300) gals
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EQUATIOn:
active + active = active
x+90=0.4x+120
0.6x=30
x=50 gallons of pure antifreeze must be added
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Cheers,
Stan H.</PRE>