Question 789361
How many litres of pure antifreeze must be added to 6 litres of a 10% antifreeze solution to obtain a 20% anitfreeze solution. 
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Equation:
anti + anti = anti
0.10*6 + 1*x = 0.20(6+x)
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10*6 + 100x = 20*6 + 20x
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80x = 10*6
x = (1/8)6
x = 0.375 litres (amt of pure antifreeze to add)
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Cheers,
Stan H.
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