The picture shows a rectangular window with a length of 120 cm. The perimeter of the window is 400 cm. What is the width of the window?
Let the width of the window be x cm.
Given:
Length = 120 cm
Perimeter = 400 cm
Perimeter of a rectangle = 2(length + width)
400 = 2(120 + x)
400 = 240 + 2x
2x = 400 - 240
2x = 160
x = 80
Therefore, the width of the window is 80 cm.