There are 500 red-crowned cranes in our country, accounting for about 1/4 of the world's first-class protected animals. How many are there in other countries?
我国有国家一级保护动物丹顶鹤500只，约占世界的(1/4)，其他国家共有多少只．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">500 / (1/4)</gadget>
<output>2_000</output>

<gadget id="calculator">2_000 - 500</gadget>
<output>1_500</output>

<result>1_500</result>