Question 272620
A chef is using a mixture of two brands of Italian dressing. The first brand contains 5% vinegar, and the second brand contains 10% vinegar. The chef wants to make 270 milliliters of a dressing that is 6% vinegar. How much of each brand should she use? 

Let x be the quantity of 5% vinegar

5%------------------------- 10%---------------------- 6% mix
x---------------------------270-x---------------------270

0.05x+0.1*(270-x) = 0.06 * 270

0.05x+27-0.1x= 16.2

- 0.05x = 16.2-27

-0.05x= -10.8

x= -10.8/ - 0.05

x=216 ml