In how many ways can three people divide 25 pieces
of candy so that each person gets at least one
piece?
Not all of the pieces must be distributed. For
example, one way that the candy can be distributed
is each person getting one piece.
Solution:
There are 2,300 ways to distribute the pieces of candy! (there are 276 different ways to distribute ALL 25 pieces).
You can distribute 3 pieces of candy in only one way.
You can distribute 4 pieces of candy in 3 ways: 1-1-2; 1-2-1; 2-1-1
You can distribute 5 pieces of candy in 6 ways: 1-1-3; 1-3-1; 3-1-1; 2-2-1; 2-1-2; 1-2-2 Prepare a table to help analyze the results:
Number of pieces of candy |
Number of ways to distribute |
3 | 1 |
4 | 3 |
5 | 6 |
6 | 10 |
7 | 15 |
... | ... |
n | (n-1)(n-2) / 2 |
(24)(23) / 2 = 12 x 23 = 276
1 + 3 + 6 + 10 + ... + 276 = 2,300
Correctly solved by:
1. Michael Leatherman | Norfolk, VA |