A chef is going to use a mixture of two brands of Italian dressing.

Question

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 340 millilitres of a dressing that is 13% vinegar. How much of each brand should she use?

Answer 1

X is the amount of the 9% vinegar

Y is the amount of the 14% vinegar

X+Y = 340

The vinegar is 0.09X + 0.14Y = 0.13*340 = 44.2

0.09X + 0.14 (340-X) = 44.2

0.09X + 47.6 - 0.14X = 44.2

-0.05x + 47.6 = 44.2

-0.05x = -3.4

5x = 340

x = 68

this forces y= 272

0.09 * 68 + 0.14 * 272 = 44.2 <--- YES IT CHECKS