The area of a rectangle is 12 square centimeters. If the length remains the same and the width is tripled, what is the area of the rectangle?
一个长方形的面积是12平方厘米，如果长不变，宽扩大3倍，这个长方形的面积是多少平方厘米．
<gadget id="calculator">12 * 3</gadget>
<output>36</output>

<result>36</result>