Question 6918
The reason why the info about the distance between the field and the fence is important is because the fence is not being built along the edge of the football field. The problem doesn't ask how many feet of fence will be needed if the fence were to be put up right along the border; It asks you to take into consideration the spacing distance that will be used. 

So let's solve this problem!

1.  we know that the field measures 360 ft by 150 ft.  
2.  The perimeter of the football field is 360 + 150 + 360 + 150
3.  We need to add the distance between the sides and the fence: so (360+45) + (150+60) + (360+45) + (150+60)     or: 2(360+45) + 2(150+60)
4.  405ft + 210ft + 405ft + 210ft= 1230ft    or: 2(405)+2(210)= 810+420=1230ft

1230 feet of fence will be needed.