Answer:
The area of the room and its uncertainty in square meters is:
15.642±0.040 
Step-by-step explanation:
We know the area of a rectangular room is the multiplication of the length and width:

Now we need to know the uncertainty, the uncertainty of a multiplication is:
(1)
: Area uncertainty
: Length uncertainty
: Width uncertainty
A: Area of the room
L: Length
W: Width
Clearing the uncertainty of the area:
(2)


The area of the room and its uncertainty in square meters is:
15.642±0.040 