1. Suppose you surround a single brown tile with 8 white tiles to form a 9 square. How many white tiles are needed to surround a 2 x 2 square of brown tiles? A 3 x 3 square of brown tiles? Continue this pattern and complete a table showing the number of brown tiles, the number white tiles and the total number of tiles at each stage.

2. Explain in words, using mathematical language, how you can determine the number of brown tiles, white tiles and total tiles needed to surround an n x n square of brown tiles.

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