A 1 yuan coin weighs about 6 grams, and 1.5 billion such coins weigh about how many tons.
一枚1元硬币约重6克，15亿枚这样的硬币约重多少吨．
<gadget id="calculator">6 * 1_500_000_000</gadget>
<output>9_000_000_000</output>

<gadget id="calculator">9_000_000_000 / 1_000_000</gadget>
<output>9_000</output>

<result>9_000</result>