One batch of goods can be transported by one large truck and two small trucks at one time (3/10), for example, four large trucks and five small trucks can be used to transport this batch of goods at one time. Question: Only one type of truck is used to transport this batch of goods. How many more small trucks are used than large trucks?
用大卡车1辆和小卡车2辆一次能运走一批货物的(3/10)，如用大卡车4辆和小卡车5辆一次恰好运完这批货物．问：只用一种卡车运这批货物，小卡车要比大卡车多用几辆？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">10 / (2/3)</gadget>
<output>15</output>

<gadget id="calculator">5 / 3</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">10 / (5/3)</gadget>
<output>6</output>

<gadget id="calculator">15 - 6</gadget>
<output>9</output>

<result>9</result>