Your lab instructor recently learned the following joke: “Did you hear about the guy who invented knock-knock jokes? He won the No-Bell prize!”. With great enthusiasm he starts telling this joke to his class of 65 students each day they come to class. He noticed that only some of the students got the joke the first time he tells it, but each subsequent time he tells it more of them understand the humor and laugh at it. However, after a while the students don't seem to be quite as amused by hearing the same joke over and over again and not as many keep laughing at it as time goes on.
Your instructor made sure to record how many students laughed at his joke each time he told it, and he recorded notes related to each telling of the joke. The data he collected for his first 10 tellings of the joke is as follows:
| Attempt | # Who Laughed | Notes |
| 1 | told to students in class | |
| 2 | told to students in same class again | |
| 3 | told to students in same class again | |
| 4 | told to students in same class again | |
| 5 | told to students in same class again | |
| 6 | told to students in same class again | |
| 7 | told to students in same class, who were also joined by students from another class this particular day | |
| 8 | told to regular students in same class again | |
| 9 | told to regular students in same class again | |
| 10 | told to regular students in same class again |