I have a question about problem 9 in chapter 7 of the FDP strategy guide (new edition).
When filling out the chart with the information, (.5)(100+x) is put in the total column because you want a mix of 50% millet in the new birdseed, correct?
Correct. (100+x) will be the total amount of birdseed and since you want 50% of that total to be millet, you leave (.5)(100+x) in both millet and other stuff columns to represent the two halves of the total.