How do i regrout tiles in bathroom?

a) Find a recurrence relation for the number of ways to lay out a walkway with slate tiles if the tiles are red, green, or gray, so that no two red tiles are adjacent and tiles of the same color are considered indistinguishable. b) What are the initial conditions for the recurrence relation in part (a)? c) How many ways are there to lay out a path of seven tiles as described in part (a)? | Numerade

Moving house: How to Easily Regrout Tiles Yourself with Dremel | Dremel

How to re-grout tiles at B&Q