Question 761125
Length = x
Width = x/3
Perimeter = 2*length + 2*width
      80 = 2(x) + 2(x/3)
      80 = 2x + 2x/3
Common denominator = 3
      240 = 6x + 2x
        8x = 240
         x = 30
Therefore the width - x/3 = 30/3 = 10 units
Hope this helps.
:-)