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.
\(A =(L)(W)\)
\(12m^{2} =(3m)(W)\)
\(\dfrac{12m^{2}}{3m} =W\)
\(4m =W\)
Hence the answer is 4m.
