A piece of rectangular paper can be cut into two square pieces of paper with a side length of 5 cm. What is the circumference of this piece of paper in cm?
一张长方形纸可以裁成两张边长为5厘米的正方形纸，原来这张纸的周长是多少厘米．
<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<gadget id="calculator">10 + 5</gadget>
<output>15</output>

<gadget id="calculator">15 * 2</gadget>
<output>30</output>

<result>30</result>