Discrete Mathematics

# Walking in a Rectangular Grid Warmup

As a tourist in NY, I want to go from the Grand Central Station (42nd street and 4th Avenue) to Times Square (47th street and 7th Avenue). I promised to meet up with my friend who was at 42nd street and 7th avenue

If I only walk West and North, how many ways are there for me to get there?

As a tourist in NY, I want to go from the Grand Central Station $$(42^\text{nd}$$ street and $$4^\text{th}$$ avenue$$)$$ to Times Square $$(47^\text{th}$$ street and $$7^\text{th}$$ avenue$$).$$

If I only walk West and North, how many ways are there for me to get there?

As a tourist in NY, I want to go from the Grand Central Station (42nd street and 4th Avenue) to Times Square (47th street and 7th Avenue). I needed my morning coffee, and wanted to go to a Starbucks that's located at 44th street and 5th avenue.

If I only walk West and North, how many ways are there for me to get there?

As a tourist in NY, I want to go from the Grand Central Station (42nd street and 4th Avenue) to Times Square (47th street and 7th Avenue). I had to drop by the ATM, which was located on 5th Avenue, between 44th and 45th street.

If I only walk West and North, how many ways are there for me to get there?

As a tourist in NY, I want to go from the Grand Central Station (42nd street and 4th Avenue) to Times Square (47th street and 7th Avenue). Due to some police activity, the intersection at 45th street and 6th Avenue is closed off, and I cannot walk through it.

If I only walk West and North, how many ways are there for me to get there?

×