The ocean area on the earth's surface is about 361 million square meters, which is 2.12 square meters more than the land area. How many billion square meters is the entire earth's area?
地球表面的海洋面积约有3.61亿平方米，比陆地面积多2.12平方米，整个地球面积约是多少亿平方米？
<gadget id="calculator">3.61 - 2.12</gadget>
<output>1.49</output>

<gadget id="calculator">1.49 + 3.61</gadget>
<output>5.1</output>

<result>5.1</result>