The world's ocean area accounts for about 70% of the earth's surface area, and the rest is land. What percentage of the earth's surface area does the land area account for?
世界海洋面积约占地球表面积的70%，其余是陆地，陆地面积约占地球表面积的百分之几？
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 - (7/10)</gadget>
<output>3/10 = around 0.3</output>

<result>3/10 = around 0.3</result>