Sack Lunches

A group of 10 students get onto a bus for a field trip and put their lunches into a cooler. Later in the day, at lunch time, the class sponsor reaches in, randomly grabs a lunch, and hands it to each student that arrives randomly.

Did anyone get their lunch?

Hint: Suppose there wer three students and three lunches.Generate the different possible combinations of students and lunches.

Students | Lunches | |||||

1 | 1 | 1 | 2 | 2 | 3 | 3 |

2 |
2 | 3 | 1 | 3 | 2 | 1 |

3 | 3 | 2 | 3 | 1 | 1 | 2 |

Dr. Robert Sweetland's Notes ©