Hello!
First you have to find the area of the floor
To do this you multiply the sides
4 * 4 = 16
Next you find the area of the rug which is a circle
The equation for this is A =

r is radius
Put in the values you know

A = 7.07
Subtract this by the area of the floor
16 - 7.07 = 8.93
The answer is 8.93m squared
Hope this helps!