If a piece of white paper is cut into a square with a side length of 4 cm, exactly 20 pieces will be cut. If the area to be cut is a right triangle of 4 square centimeters, how many pieces can be cut.
一张白纸，若裁成边长是4厘米的正方形，正好裁20块．若裁面积是4平方厘米的直角三角形，可裁多少块．
<gadget id="calculator">4 * 20</gadget>
<output>80</output>

<result>80</result>