If the length and width of a rectangle with a circumference of 3 decimeters are increased by 4 centimeters, how many square centimeters will the area of the new rectangle be larger than the area of the original rectangle?
把一个周长三分米的长方形的长、宽各增加4厘米，新长方形的面积比原长方形的面积大多少平方厘米？
<gadget id="calculator">30 / 2</gadget>
<output>15</output>

<gadget id="calculator">3 * 15</gadget>
<output>45</output>

<gadget id="calculator">45 + 9</gadget>
<output>54</output>

<result>54</result>