Please help me solve this question:
The kitchen floor of Emily’s house is made from 40 square tiles, as shown below:
(Picture: http://hkgshare.com/di-YMJT.png)
As the tiles become worn out over the years, Emily decided to replace them. Unfortunately, she was only able to obtain matching rectangular tiles. Each rectangular tile will cover exactly two of the original square tiles.
Is it possible for Emily to replace all the original square tiles with the new rectangular tiles and fit the kitchen floor exactly? Explain.
(Hint: Colour kitchen floor as a checkerboard.)