Question 810499
Question : how much water must you add 
100 mL of orange juice concentrate if you
Want your final juice to be 20%.
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water + water = water
0*100 + 1*x = 0.20(100+x)
100x = 20*100 + 20x
80x = 2000
x = 25 mL (amt. of water needed)
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Cheers,
Stan H.
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