Algebra question

Question

A chef plans to mix 100% vinegar with Italian dressing. The Italian dressing contains 8% vinegar. The chef wants to make 60 milliliters of a mixture that contains 31% vinegar. How much vinegar and how much Italian dressing should she use?

Answer 1

Let x = number of milliliters of pure vinegar  

 

Then, 60 - x = number of milliliters of dressing that is 8% vinegar

 

(vinegar content of pure vinegar) + (vinegar content of 8% vinegar dressing) = (vinegar content of mixture)

 

1.00x + 0.08(60-x) = 0.31(60)

 

      x + 4.8 - 0.08x = 18.6

 

                    0.92x = 13.8

 

                          x = 15 ml

 

Use 15 ml of pure vinegar and 45 ml of the 8% type of dressing.