Acertain drug is made from only two ingredients: compound a and compound
b. there are 5 milliliters of compound a used for every 4 milliliters of compound
b. if a chemist uses 460 milliliters of compound a, how many milliliters of the drug will be made?

Compound a                                        Compound b
5 mil                                                             4 mil

We can write this as a ratio- 5:4
So basically it takes 9 mil of both combined to make one drug 
You can divide 460/9 for your

460/9= 51.(1)                      ( )= repeating decimal
So basically 52 drugs
hope this helps!