SOLUTION: how many quarts of type P punch, which is 3% alcohol and type Q punch, which is 8% alcohol, should be combined to get 20 quarts of punch that is 6% alcohol?

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Question 973979: how many quarts of type P punch, which is 3% alcohol and type Q punch, which is 8% alcohol, should be combined to get 20 quarts of punch that is 6% alcohol?
Found 2 solutions by stanbon, Boreal:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
how many quarts of type P punch, which is 3% alcohol and type Q punch, which is 8% alcohol, should be combined to get 20 quarts of punch that is 6% alcohol?
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Equation:
alch + alch = alch
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0.03p + 0.08(20-p) = 0.06*20
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3p + 8*20 - 8p = 6*20
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-5p = -2*20
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p = 8 qts (amt. of P punch needed)
20-p = 12 qts (amt of Q punch needed)
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Cheers,
Stan H.

Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website!
p=P punch in quarts
q=Q punch in quarts
Because the final amount is closer to Q than to P, expect Q to be larger.
.03P+ .08(20-P)=.06 *20 =1.2 alcohol-quarts unit
.03P +1.6-.08P=1.2
-.05P=-.4
divide both sides by -.05
P=8 quarts
Q=12 quarts
.03*8 + .08*12= .24+.96=1.2