There are about 4,000 species of mammals in the world, of which my country accounts for about 12.5%. How many species of mammals are there in my country?
全世界哺乳动物约有4000种，其中我国约占12.5%，我国哺乳动物约有多少种．
<gadget id="calculator">12.5 / 100</gadget>
<output>0.125</output>

<gadget id="calculator">4_000 * 0.125</gadget>
<output>500</output>

<result>500</result>