The earth's surface area is 510 million square kilometers, of which the ocean area is 361 million square kilometers, and the rest is land area. How many square kilometers is the earth's land area less than the ocean area?
地球表面积是5.1亿平方千米，其中海洋面积是3.61亿平方千米，剩余的是陆地面积．地球陆地面积比海洋面积少多少平方千米？
<gadget id="calculator">5.1 - 3.61</gadget>
<output>1.49</output>

<gadget id="calculator">3.61 - 1.49</gadget>
<output>2.12</output>

<result>2.12</result>