The perimeter of a rectangular metal sheet is 280 cm. If its length is 80 cm, then what is the area of the metal sheet?

The perimeter of the rectangular metal sheet = 280 cm.

The length of the rectangular metal sheet = 80 cm.

Perimeter of rectangle = 2(length + breadth) 

∴ 2(length + breadth) = 280 cm

⇒ length + breadth = $\frac{280}{2}$ = 140 cm

⇒ 80 + breadth = 140 cm

∴ Breadth = 140 cm − 80 cm = 60 cm

Area of the rectangular metal sheet = length × breadth 

                                                                       = 80 cm × 60 cm 

                                                                       = 4800 cm².

The area of the rectangular metal sheet is 4800 cm².