A number of vehicles shipped a batch of goods. If each vehicle loads 3.5 tons, 2 tons of this batch of goods cannot be transported away; if each vehicle loads 4 tons, after loading this batch of goods, 1 ton of other goods can be loaded. How many tons is this shipment?
汽车若干辆装运一批货物．如果每辆装3.5吨，这批货物就有2吨不能运走；如果每辆装4吨，装完这批货物后，还可以装其他货物1吨．这批货物有多少吨？
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">4 - 3.5</gadget>
<output>0.5</output>

<gadget id="calculator">3 / 0.5</gadget>
<output>6</output>

<gadget id="calculator">4 * 6</gadget>
<output>24</output>

<gadget id="calculator">24 - 1</gadget>
<output>23</output>

<result>23</result>