The width of a rectangle is 12m and the length is 4 times the width. What is the area of the rectangle in square meters?
一个长方形的宽是12m，长是宽的4倍．长方形的面积是多少平方米？
<gadget id="calculator">12 * 4 * 12</gadget>
<output>576</output>

<result>576</result>