Can someone do this question please ? I can't do it.
Prove that if |A| ≤ |B| and |B| ≤ |C| then |A| ≤ |C|
Note: |A| ≤ |B| means "there exist an injection from set A into set B" and so on for the rest.
I would really appreciate it if someone can help me because I find this very hard.