"Propagate the error in the theoretical value of the area of the table." How do I calculate this?

Experiment 2: Area measured with a 2-m metric ruler. Uncertainty in the length (Al) and width (Aw) is 1 mm = 0.1 cm. Calculate the mean value of area of the table: It will serve as your theoretical value of Area ( Athear ). Length X Width - 183.0 X 76.2 = 13944.6 cm2 OR 139 X102 cm2 Propagate the error in the theoretical value of area of the table