12.

For the Spring Fling gala, Felicia has 500 ft of lights to hang. If the width of the

room is 70 ft, what is the length of the room if she can hang all the lights so

that they go around the room exactly once?

Length of the room is 180 ft

Step-by-step explanation:

We have a rectangular room with dimensions:

width = 70 ft and length "x" (unknown)

Perimeter of a rectangle is 2*w + 2*x and according to problem statement 500 ft of lights will fit exactly in room perimeter then:

2*70 + 2*x = 500

140 + 2*x = 500

2*x = 500 - 140

2*x = 360

x = 360/2

x = 180 ft