Question 392626
 Your lawn mower requires an oil and gas mixture to make it run correctly. 
The mixture requires 3 times as much gas as oil.
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g = 3o
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Gas costs $1.43 and oil costs $.85 a gallon.
Value: 1.43g + 0.85o <= 20
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How many full gallons of the mixture can be made for $20?
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Substitute for "g" and solve for "o":
1.43(3o) + 0.85o <= 20
5.14o <= 20
o <= 3.89 gallons of oil
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solve for "g"
(g/3) <= 3.89
g <= 11.67 gallons of gas
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Cheers,
Stan H. 
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