A rectangular land is 16 kilometers long and four times as long as it is wide. What is the area of the land in square kilometers?
一个长方形地块长16千米，长是宽的4倍，这块地的面积是多少平方千米．
<gadget id="calculator">16 / 4</gadget>
<output>4</output>

<gadget id="calculator">16 * 4</gadget>
<output>64</output>

<result>64</result>