Question

What is the first step in the indirect proof?
a. Given: There are 12 dogs and cats at a veterinarian’s office. There are more dogs than cats.
Prove: There are at least 7 dogs.
b. Given: an integer n
Prove: n is odd

Answer 1

A) If you have 12 dogs and cats (I assume 12 in total) and divide those by two, you get six dogs and six cats. It has to be more dogs than cats, and the sum of those two has to be twelve. So to reach the sum 12, while one number is bigger that the other, the number has to be 7 or more.