The formula for perimeter is P = 2length + 2width (P = 2L + 2W)
You know that the length is 27 ft but you don't know the width. To find the width plug 90 in for P and 27 in for L then solve for W.
90 = 2(27) + 2W
90 = 54 + 2W
90 - 54 = 54 - 54 + 2W
36 = 0 + 2W
36 = 2W
36 / 2 = 2W/ 2
18 = 1W
18 = W
Width is 18 ft
Check:
2(27) + 2(18) = 90
54 + 36 = 90
90 = 90
Hope this helped!
~Just a girl in love with Shawn Mendes
