A five-cent coin weighs about 4 grams. According to this calculation, how many tons does 100 million five-cent coins weigh?
一枚五角硬币大约重4克，照这样计算，1亿枚五角硬币大约重多少吨．
<gadget id="calculator">100_000_000 / 1_000_000</gadget>
<output>100</output>

<gadget id="calculator">4 * 100</gadget>
<output>400</output>

<result>400</result>