The length and breadth of rectangular cardboard are 40 cm and 35 cm, respectively. If the biggest possible square is cut out from this cardboard, what is the area of the remaining part of the cardboard?

The length and breadth of rectangular cardboard are 40 cm and 35 cm, respectively.

area of rectangular cardboard = $$length \times breadth$$

= $$40 \times 35$$

= 1400 $$cm^2$$

If the biggest possible square is cut out from this cardboard, then the length of each side of this square will be equal to 35 cm.

Area of square = $$\left(length\ of\ each\ side\right)^2$$

= $$(35)^2$$

= 1225 $$cm^2$$

Area of the remaining part of the cardboard = area of rectangular cardboard - area of square

= 1400-1225

= 175 $$cm^2$$