The fruit shop shipped 30 baskets of fruit, each weighing 20 kilograms, and the number of kilograms to be shipped was exactly 1 ton.
水果店运来水果30筐，每筐重20千克，还要运多少千克就正好是1吨．
<gadget id="calculator">1 * 1_000</gadget>
<output>1_000</output>

<gadget id="calculator">20 * 30</gadget>
<output>600</output>

<gadget id="calculator">1_000 - 600</gadget>
<output>400</output>

<result>400</result>