The answer is: Chunking.
People are known to chunk when they are wanting to remember something so, they keep repeating what they want to remember over and over again so they won't forget.
Chunking is a way for someone to remember, which is known to work most of the time.
Chunking is basically when you are repeating yourself in till you remember what you needed to remember such as: Numbers, pins, rules, etc.
Chunking is a very common way to remember something without writing it on paper especially when you don't want someone else to know.
(Completed question with answer):
As soon as Carol heard the phone number on the radio for a chance to win free concert tickets, she raced to the phone repeating out loud, “555-23-47,” so she wouldn’t forget before dialing. This is an example of Chunking.
I hope this help's you understand!
-LizzyIsTheQueen