Area of the window= 400 square inches
Let the width of the window be 'x' inches,
then the height of the window will be 12 times 'x' inches.
We know, Area of the window= width X height
therefore, 400= x inches X 12x inches
=>400=12[tex]x^2[/tex] inches
=>[tex] x^{2} [/tex]=400/12 inches
=>x=5.77 inches
Therefore, width=5.77 inches and height=12X5.77=69.28 inches