The per capita arable land area in the United States is 90,000 square meters. The per capita arable land area in the world is 1/3 of that of the United States, while China is a country with very little per capita arable land area in the world, only 2/5 of the world's per capita arable land area.
美国人均耕地面积90000平方米．全世界人均耕地面积是美国的(1/3)，而中国是全世界人均耕地面积非常少的国家，只有世界人均耕地面积(2/5)，中国人均耕地面积是多少平方米？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">90_000 * (1/3) * (2/5)</gadget>
<output>12_000</output>

<result>12_000</result>