Answer:
346 cm²
Step-by-step explanation:
Area of square:
Area = [tex]Length*Length[/tex]
A = 20*20
A = 400 cm²
Area of rectangle:
Length = 3 cm
Width = 20-2 = 18 cm
Now, The Area:
Area = [tex]Length * Width[/tex]
Area = 3 * 18
Area = 54 cm²
Now, The difference in their areas:
=> 400-54
=> 346 cm²
