If the ratio of length to width is 2:7, then you can create a variable x to determine the multiplier that gets you the length and width. So the length is 2x and the width is 7x. So the perimeter equation is...
P=2L+2W
P=2(2x)+2(7x)
333=4x+14x
333=18x
x=18.5
Since the width is 7x, it’s just 7(18.5)=129.5 cm.
