<PRE><B>Question 466239</B>
Automotive maintenance. The radiator in Natalie’s car contains 6.3 L of antifreeze and water. This mixture is 30% antifreeze. How much of this mixture should she drain and replace with pure antifreeze so that there will be a mixture of 50% antifreeze.
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alcohol -alcohol + alcohol = alcohol
0.30*6.3 -0.30x + 1.00x = 0.50*6.3
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Multiply thru by 100 to get:
30*6.3 - 30x + 100x = 50*6.3
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70x = 20*6.3
x = (2/7)6.3
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x = 2*0.9
x = 1.8 Liters (amt. of mixture that should be removed and replaced).
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Cheers,
Stan H.
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