SOLUTION: A chef is going to use a mixture of two brands of Italian dressing. The first brand contains 7% vinegar, and the second brand contains 15% vinegar. The chef wants to make 2

Algebra ->  Graphs -> SOLUTION: A chef is going to use a mixture of two brands of Italian dressing. The first brand contains 7% vinegar, and the second brand contains 15% vinegar. The chef wants to make 2      Log On


   

Question 1148603: A chef is going to use a mixture of two brands of Italian dressing. The first brand contains
7%
vinegar, and the second brand contains
15%
vinegar. The chef wants to make
240
milliliters of a dressing that is
14%
vinegar. How much of each brand should she use?

Found 2 solutions by greenestamps, josgarithmetic:
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Algebraically....

x ml of 7%, plus (240-x) ml of 15%, equals 240 ml of 14%:

x%28.07%29%2B%28240-x%29%28.15%29+=+240%28.14%29

Straightforward basic algebra; but a bit time-consuming.

Here is a much faster and easier way to solve a "mixture" problem like this....

14% is 7/8 of the way from 7% to 15%. (7 to 15 is 8; 7 to 14 is 7; 14 is 7/8 of the way from 7% to 15%.)

That means 7/8 of the mixture should be the brand with the higher percentage.

7/8 of 240 ml is 210 ml. So

ANSWER: 210 ml of the 15% brand; the other 30 ml of the 7% brand.

Answer by josgarithmetic(39617) About Me  (Show Source):