SOLUTION: How many ounces of pure bran flakes must be added to 70 ounces of cereal that is 42% bran flakes to produce a mixture that is 59.4% bran flakes?

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: How many ounces of pure bran flakes must be added to 70 ounces of cereal that is 42% bran flakes to produce a mixture that is 59.4% bran flakes?      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 712337: How many ounces of pure bran flakes must be added to 70 ounces of cereal that is 42% bran flakes to produce a mixture that is 59.4% bran flakes?
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
u = how many ounces of pure bran

%28100u%2B70%2A42%29%2F%28u%2B70%29=59.4

100u%2B70%2A42=59.4%28u%2B70%29
100u%2B70%2A42=59.4u%2B59.4%2A70
100u-59.4u=59.4%2A70-42%2A70
%28100-59.4%29u=%2859.4-42%2970
u=70%2859.4-42%29%2F%28100-59.4%29
u=30
Add 30 ounces of pure bran to the 70 ounces of 42% bran to get 59.4% bran.