Xiaojun goes swimming. He swims 2 back and forth in the swimming lane for a total of 100 meters. How long is the swimming lane in this swimming pool?
小军去游泳，他在泳道内游2个来回，共游100米，这个游泳池的泳道长多少米米．
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">100 / 4</gadget>
<output>25</output>

<result>25</result>