What is the perimeter in centimeters of a large square made of 4 small squares with sides of 3 centimeters?
用4个边长为3厘米的小正方形拼成的大正方形的周长是多少厘米．
<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<result>24</result>