The earth's surface (29/100) is land, and the rest is ocean. How much more is the ocean area than the land area?
地球表面(29/100)是陆地，其余是海洋，海洋面积比陆地面积多多少？
<gadget id="calculator">29 / 100</gadget>
<output>29/100 = around 0.29</output>

<gadget id="calculator">1 - (29/100) - (29/100)</gadget>
<output>21/50 = around 0.42</output>

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