A certain 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 308 milliliters of compound b, how many milliliters of the drug will be made?

To find how many milliliters of the drug will be made, you will use proportions to solve for how much of compound a you will need with the indicated amount for compound b.

compound a 5 mL x 77 385 ml

compound b 4 ml x 77 308 ml

Add the two amounts together to get a total: 385 + 308 = 693 mL

There will be 693 mL of the drug.