SOLUTION: A doctor prescribes an ointment that is 5% hydrocortisone. A pharmacist has 1% and 9% concentrations in stock. How many ounces of each should the pharmacist use to make a 1-ounce t

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: A doctor prescribes an ointment that is 5% hydrocortisone. A pharmacist has 1% and 9% concentrations in stock. How many ounces of each should the pharmacist use to make a 1-ounce t      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 401697: A doctor prescribes an ointment that is 5% hydrocortisone. A pharmacist has 1% and 9% concentrations in stock. How many ounces of each should the pharmacist use to make a 1-ounce tube?

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=the amount of 1% that is required and 1-x the amount of 9% required.
.01x+.09(1-x)=.05
.01x+.09-.09x=.05
-.08x+.09=.05
-.08x=-.04
x=.5 oz.
.
Ed