Question 284774
How much water must a landscaper add to a 10% solution of selective herbicide to create 5 gallons of 4% solution? 
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Equation:
water + water = water
x + 0.90(5-x) = 0.96*5
Multiply thru by 100 and solve for "x":
100x + 90*5 - 90x = 96*5
10x = 6*5
x = 3 gallons (amt. of water needed for the mixture)
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How much of the 10% solution did the landscaper have before he added the water?
What does that mean?
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Cheers,
Stan H.