What is the perimeter of a 4 by 6 foot window?

To calculate the perimeter of a rectangle, you use the formula ( P = 2 \times (length + width) ). For a 4 by 6 foot window, the perimeter would be ( P = 2 \times (4 + 6) = 2 \times 10 = 20 ) feet. Therefore, the perimeter of the window is 20 feet.