Question 644232
find the concentration of sugar as percent when 20 gram sugar mixed in 60 grams water ,how many more grams of sugar has to be added to make it 30% solution 
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Concentration = 20/80 = 25%
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Equation:
sugar + sugar = sugar
25%*80 + x = 0.30(80+x)
25*80 + 100x = 30*80 + 30x
70x = 5*80
x = 400/70 = 5.71 grams (amt of sugar to add)
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Cheers,
Stan H.
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