Question 20
Donald had a square sheet of paper. He cut along the dotted line to remove four corners and obtained a smaller square with perimeter 40 cm. Find the area of the original sheet in $\mathrm{cm}^2$.
Editorial clarification: the cuts pass through the midpoints of all four sides of the original square. This convention follows the picture’s intended layout; the original wording and figure have no explicit midpoint marks.
Editorial clarification: the cuts pass through the midpoints of all four sides of the original square. This convention follows the picture’s intended layout; the original wording and figure have no explicit midpoint marks.