A construction site originally had 30 tons of cement, and another 6,000 kilograms of cement was shipped in, which was just enough for 9 days. How many tons of cement does this construction site use on average every day?
一建筑工地原有水泥30吨，又运来6000千克水泥，这些水泥刚好够用9天．这个工地平均每天用几吨水泥？
<gadget id="calculator">6_000 / 1_000</gadget>
<output>6</output>

<gadget id="calculator">30 + 6</gadget>
<output>36</output>

<gadget id="calculator">36 / 9</gadget>
<output>4</output>

<result>4</result>