About (71/100) of the Earth's surface is covered by oceans, and the rest is land. By what percentage of the Earth's surface is the ocean area greater than the land area?
地球表面大约有(71/100)被海洋覆盖，其余的是陆地．海洋面积比陆地面积多地球表面积的几分之几？
<gadget id="calculator">71 / 100</gadget>
<output>71/100 = around 0.71</output>

<gadget id="calculator">1 - (71/100)</gadget>
<output>29/100 = around 0.29</output>

<gadget id="calculator">(71/100) - (29/100)</gadget>
<output>21/50 = around 0.42</output>

<result>21/50 = around 0.42</result>