Problems: Problem Set #27
Answers: Problem Set #27_Answers
Note: Problem 1 was a puzzler from the NPR show Car Talk. They solved it in a slightly different way than I did. You can read their solution here: http://cartalk.com/content/puzzler/transcripts/201101/answer.html
Also, I left out an important condition in my original problem statement. You must purchase at least one of each type of animal, so zero dogs, zero mice, and 100 cats is not the right answer. Sorry about that.