If a batch of cement is shipped 3,000 tons each time, it can be shipped 20 times. If an extra 1,000 tons is shipped each time, how many times can it be shipped?
运一批水泥，如果每次运3000吨，20次可以运完，如果每次多运1000吨，几次可以运完、？
<gadget id="calculator">3_000 + 1_000</gadget>
<output>4_000</output>

<gadget id="calculator">20 / 4_000</gadget>
<output>1/200 = around 0.005</output>

<gadget id="calculator">3_000 * (1/200)</gadget>
<output>15</output>

<result>15</result>