Miguel has to color 4 squares out of 8:
He can color one square with blue, one square with red, and two squares with green.
One correct answer is:
2/8 green, 1/8 red, and 1/8 blue.
If there are 8 tiles, coloring 4/8 means coloring 4 tiles. Using those three colors, we could use each 1 time with 1 left over. Since we must have more green, we would use it twice; this would give us 2 green, 1 red and 1 blue.
Since the grid is not necessarily 8 squares, we must account for this by saying 2/8 green, 1/8 red and 1/8 blue.