More Help Please

[HABS]

When tiling the square wall of my kitchen, I use red and blue square tiles
all of the same size. In the pattern all the tiles are red apart from those on the two diagonals which are blue. If I use 37 blue tiles, how many red tiles are needed?

[SteveDH]

Its square
the blue tiles are in the diagonals
there are an odd number of blue tiles so the center tile is shared.

the number of tiles in a diagonal is the same as the number of tiles in an edge.


so (37 +1)/2 will give us the length of an edge (+1 for shared tile)

so length of edge is 19 tiles

19x19= 361 total tiles

red tiles = 361-37 = 324 tiles

[chad]

Possibly...
Each diagonal line (set in a cross) would be 19 squares therefore I would assume wall would be 19 x19 = 361 tiles. 361 - 27 (blue tiles) = 324.
(havent double checked the figures.)