The area of the floor is 10 m x 8 m = <<10*8=80>>80 square meters.
The area of the carpet is 4 m x 4 m = <<4*4=16>>16 square meters.
Therefore, the area of the floor not covered by the carpet is 80 square meters - 16 square meters = <<80-16=64>>64 square meters,
#### 64