Uncle Wang rode a motorcycle with the wind for 100 kilometers in 2 hours, and the wind speed is 5 kilometers per hour, so how many kilometers does the motorcycle travel against the wind?
王叔叔顺风骑摩托车2小时行了100千米，风速是每小时5千米，那么这辆摩托车逆风行驶的速度是多少千米？
<gadget id="calculator">100 / 2</gadget>
<output>50</output>

<gadget id="calculator">50 - 5 - 5</gadget>
<output>40</output>

<result>40</result>