SOLUTION: one grade of oil has 0.50% of an additive, and a higher grade has .75% of the additive. How many liters of each must be used to have 1000L of a mixture with 0.65% of the additive?

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Question 68704: one grade of oil has 0.50% of an additive, and a higher grade has .75% of the additive. How many liters of each must be used to have 1000L of a mixture with 0.65% of the additive?


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Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
one grade of oil has 0.50% of an additive, and a higher grade has .75% of the additive. How many liters of each must be used to have 1000L of a mixture with 0.65% of the additive?
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Let amount of 0.50% oil be "x" liters ; amt. of additive is 0.005x L
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Amt of 0.75% oil is "1000-x"; amt. of additive is 0.0075(1000-x)=7.5-0.0075x L
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Amt of 0.65 mixture is 1000 L; amt of additive is 0.0065(1000)=6.5 L
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EQUATION:
additive + additive = additive
0.005x + 7.5-0.0075x = 6.5
-0.0025x=-1
Multiply both sides by -1000
2.5x=1000
Divide by 2.5 to get:
x=400 liters (amount of 0.50% additive oil in the mixture)
1000-400 = 600 liters (amount of 0.75% additive oil in the mixture)
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Cheers,
Stan H.