7 trucks can transport 336 tons of stones in 6 times. The existing 560 tons of stones are required to be transported in 5 times. How many more trucks need to be added?
7辆卡车6次可运走336吨石子，现有560吨石子，要求5次运完，需要增加同样的卡车多少辆？
<gadget id="calculator">336 / 6 / 7</gadget>
<output>8</output>

<gadget id="calculator">8 * 5</gadget>
<output>40</output>

<gadget id="calculator">560 / 40</gadget>
<output>14</output>

<gadget id="calculator">14 - 7</gadget>
<output>7</output>

<result>7</result>