Greetings!
Answer: 10 1/2 feet
Step-by-step explanation:
As the room is a rectangle, to find the area you simply multiply the length and width together.
L x W = A
As in the question stated you have the area and length:
12.5 x W = 131
To find the width you can simply divide the area by the length:
131 ÷ 12.5 = 10.48 ≅ 10.5 = 10
So the width is 10
feet
Hope this helps!