Answer:
[tex]20.78 \:square\:inches[/tex]
Step-by-step explanation:
The unpainted region on the four-inch board forms a parallelogram of dimension 4 inches by 6 inches.
The angle at which they cross is 60 degrees.(as shown in the diagram)
Given two sides and an included angle in a parallelogram,
Area of the parallelogram
[tex]=ab sin \theta\\a=4 inch, b= 6 inch, \theta = 60^0\\Area =4*6*sin60^0\\=20.78 \:square\:inches[/tex]
