So thi sis really simple since you have an equal sign so
(n/3)-(5n/6)=1/3
to subtract fractions, make the bottom number the same
n/3 times 2/2=2n/6
(2n/6)-(5n/6) or (2n-5n)/6 so
-3n/6=1/3
multiply both sides by 6
-3n=6/3=2
-3n=2
divide both sides by 3
-n=2/3
mmultiply boht by -1
n=-2/3
tada
n=-2/3
Josie's height = 5 ft 6 in. = 5 1/2 ft = 11/2 ft.
Josie's shadow = 6 ft.
Ratio of shadow to height = 6 / 11/2 = 12/11
So, It would be equal to ratio of building's shadow to building's height.
18/x = 12/11
x = 18*11 /12
x = 3*11 / 2
x = 16.5
In short, Your Answer would be 16.5 Feet
Hope this helps!