There are 4 tons of cement on the construction site, 3 tons are used for the first time, 200 kg are used for the second time, 75 kg are used for the third time, how many kg of cement are left?
工地上有4吨水泥，第一次用去3吨，第二次用去200千克，第三次用去75千克，还剩下多少千克水泥．
<gadget id="calculator">4 * 1_000</gadget>
<output>4_000</output>

<gadget id="calculator">3 * 1_000</gadget>
<output>3_000</output>

<gadget id="calculator">4_000 - 3_000 - 200 - 75</gadget>
<output>725</output>

<result>725</result>