The Birthday Problem (Data Sheet)

_____ people in the room

Website: http://www-stat.stanford.edu/~susan/surprise/Birthday.html

Trials
Matches
1
.
2
.
3
.
4
.
5
.
6
.
7
.
8
.
9
.
10
.
.
.
Total
.

Count the number of times you had at least one match for each trial. What is the percentage of successful matches to trials? (One or more matches counts as only one match.)

Student activity:

Have students collect data on groups of X people whose birthdates are unknown but can be ascertained. For example:

  • Presidents of the United States
  • Members of the New York Jets football team
  • Members of the New York Liberty basketball team
  • Students in your schools classrooms. (Choose X members at random from a class list and find out their birthdates.)

See actual probabilities

comments?

updated: 11/18/08