The cheerleaders are making a rectangular banner for a football game. the length of the banner is 30 ft long. the cheerleaders can use no more than 96 feet of trim around the whole banner. what are the possible widths of the banner?

GIVEN:
total length of the banner = 30 ft.
perimeter of the banner = 96 ft.
total width of the rectangle = ?
Let,
the perimeter be "p"
the length be "L"
the width be "w"
We know,
Perimeter (P) of a rectangle = 2 (L + w) 
Substituting the values of P, L and w , we get,
                                      96  = 2 (30 + w)  
                                  96 / 2 = 30 + w
                                       48 = 30 + w
                                48 - 30 = w
                                       18 = w

So, the width of the rectangular banner is 18 ft.