This is a math question, but I will give you the answer anyway:
The width of the room is 4m.
Here is how you get to the answer:
The area of the room is given, which is 12m². The m² is a dead give-away.
Now we know that the formula of the area of the room is:
A = L x W
where:
A is the Area
L is the Length
W is the width
Now all you have to do is plug in all the values that you know first into the formula and then solve for what you don't know.




Hence the answer is 4m.