The perimeter of a square is 30 cm, what is the perimeter if the side length is tripled?
正方形的周长是30厘米，如果边长扩大3倍，周长是多少．
<gadget id="calculator">30 / 4</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">(15/2) * 3 * 4</gadget>
<output>90</output>

<result>90</result>