For some number [tex]x[/tex], the side lengths are [tex]2x[/tex], [tex]3x[/tex], and [tex]4x[/tex].
The perimeter is [tex]2x+3x+4x=9x[/tex]
The shortest side is [tex]2x=15[/tex]
So [tex]x=7.5[/tex]
Plug into [tex]9x[/tex]:
[tex]9*7.5=67.5[/tex]
So the perimeter is 67.5 inches.
