SOLUTION: A mixture of 3% disinfectant solution is to be made from 5% and 2% disinfectant solutions. How much of each solution should be used if 39 gallons of 3% solution are needed?

Question 1040159: A mixture of 3% disinfectant solution is to be made from 5% and 2% disinfectant solutions. How much of each solution should be used if 39 gallons of 3% solution are needed?

Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39618)   (Show Source): You can put this solution on YOUR website!
This is a very common exercise question type.
Mixing two concentrations for known amount of mixture
video example , two part mixture problem using just one variable
Answer by ikleyn(52788)   (Show Source): You can put this solution on YOUR website!
.
On mixture word problems see the lessons
    - Mixture problems
    - More Mixture problems
    - Solving typical word problems on mixtures for solutions
    - Typical word problems on mixtures from the archive
    - OVERVIEW of lessons on word problems for mixtures
in this site.

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