The radius of the window in the living room is 8 + 4 = 12 inches.
The circumference of a circle is given by the formula C = 2πr, where r is the radius of the circle and π is the mathematical constant pi, which is approximately equal to 3.14.
Therefore, the circumference of the circular window in the living room is:
C = 2π(12) = 24π
So, the circumference of the circular window in the living room is approximately 75.4 inches (rounded to the nearest tenth).