Answer:
36 feet long
Explanation:
When you get the question it should look like this: 6/2.5 X/15.
Your gonna have to cross multiply 6 and 15 the keep 2.5 and X like this: 2.5x
After that, it should look like this: 2.5x=90, Now your gonna wanna divide 90 and 2.5 which you will get 36.
X= 36 ft long.
Hoped this helped!