There are 15 motorcycles and tricycles with 35 wheels in total. How many motorcycles are there?
摩托车和三轮车共15辆，共有35个轮子，摩托车有多少辆．
<gadget id="calculator">3 * 15</gadget>
<output>45</output>

<gadget id="calculator">45 - 35</gadget>
<output>10</output>

<gadget id="calculator">3 - 2</gadget>
<output>1</output>

<gadget id="calculator">10 / 1</gadget>
<output>10</output>

<result>10</result>