You are given an n×n board, where n is an even integer and 2≤n≤30. For how many such boards is it possible to cover the board with T-shaped tiles like the one shown? Each cell of the shape is congruent to one cell on the board.

  5

Step-by-step explanation:

The number of cells in a tile is 4, so the board dimension cannot be odd, but must be a multiple of 2 in order to have the number of cells divisible by 4.

If the tiles are colored in an alternating pattern, tiles must have 3 of one color and 1 of the alternate color. Hence the total number of tiles used to cover a board must be even (so the numbers of each color match). Then the board dimension must be divisible by 4.

In the given range, there are 5 such boards:

  4×4, 8×8, 12×12, 16×16, and 20×20

c.

step-by-step explanation: