Question 822275
How many cups of grape punch containing 10% fruit juice and berry punch containing 20% fruit juice must be added together to create 12 cups of punch with 18% fruit juice? 
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Equation:
fj + fj = fj
0.10x + 0.20(12-x) = 0.18*12
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10x + 20*12 - 20x = 18*12
-10x = -2*12
x = (1/5)12
x = 2.4 cups (amt. of 10% needed)
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12-x = 9.6 cups (amt. of 20% needed)
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Cheers,
Stan H.
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