Rembrandt framed his masterpiece. The painting by itself is a rectangle with length 20 \text{ cm}20 cm20, start text, space, c, m, end text and width 16 \text{ cm}16 cm16, start text, space, c, m, end text. The painting and frame together form a larger rectangle with length 25 \text{ cm}25 cm25, start text, space, c, m, end text and width 20 \text{ cm}20 cm20, start text, space, c, m, end text.