In the subway station, an upward escalator is erected from the platform to the ground. Xiaoqiang wants to go retrograde from top to bottom. If he steps down two steps per second, he will reach the platform after walking 100 steps; Take three steps, then walk through 75 steps to reach the platform, how many steps are there on the escalator?
在地铁车站中，从站台到地面架设有向上的自动扶梯，小强想逆行从上到下，如果每秒向下迈两级台阶，那么他走过100级台阶后到达站台；如果每秒向下迈三级台阶，那么走过75级台阶到达站台，自动扶梯有多少级台阶？
<gadget id="calculator">100 / 2</gadget>
<output>50</output>

<gadget id="calculator">100 - 75</gadget>
<output>25</output>

<gadget id="calculator">75 / 3</gadget>
<output>25</output>

<gadget id="calculator">50 - 25</gadget>
<output>25</output>

<gadget id="calculator">25 / 25</gadget>
<output>1</output>

<gadget id="calculator">50 * 1</gadget>
<output>50</output>

<gadget id="calculator">100 - 50</gadget>
<output>50</output>

<result>50</result>