Problem of the Week 1169
Roll the Dice
What is the expected number of distinct faces seen when throwing a 6-sided die n times?
Here is a related problem:
Suppose a standard die is rolled 6 times. Which is more likely: seeing 3 distinct faces or seeing 5 distinct faces?
Source: Julian Beasley; Matthew Conroy offers a nice download about dice problems.
© Copyright 2013 Stan Wagon. Reproduced with permission.