Path counting problems  Permutations and Combinations
Path counting problems
Lessons
Notes:
Regular Puzzle:

1.
Moving only the right or down, how many different paths exist to get from point A to point B?

2.
? Irregular Puzzle

3.
Below is an 8 × 8 checkerboard. The game pieces are only allowed to move diagonally and forward on the dark squares. How many possible ways are there for the checker to reach the opposite side of the game board, if: