Question 1195876
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a chef is going to use a mixture of two brands of Italian dressing. the first brand contains 9% vinegar, 
and the second brand contains 14% vinegar. the chef wants to make 360 milliliters of a dressing that is 13% vinegar. 
how much of each brand should she use?
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<pre>
Take x mL of the 14% vinegar and (360-x) mL of the 9% vinegar.


Write the volume balance equation for the pure vinegar

    0.14x + 0.09*(360-x) = 0.13*360   mL.


Simplify and find x

    0.14x + 0.09*360 - 0.09x = 0.13*360

    0.14x - 0.09x = 0.13*360 - 0.09*360

    (0.14 - 0.09)x =      14.4

         0.05x     =      14.4

             x     =      14.4/0.05 = 288 mL.


<U>ANSWER</U>.  She should take 288 mL of the 14% vinegar and (360-288) = 72 mL of the 9% vinegar.
</pre>

Solved.