The width of a rectangle is 4 cm and the length is 3 times the width, what is the area of the rectangle in cm
一个长方形的宽是4厘米，长是宽的3倍，长方形的面积是多少厘米
<gadget id="calculator">4 * 3 * 4</gadget>
<output>48</output>

<result>48</result>