Two naughty children walk in the opposite direction of the escalator. The boy can walk 3 steps per second, and the girl can walk 2 steps per second. As a result, from one end of the escalator to the other end, the boy walked for 80 seconds and the girl walked for 180 seconds. So how many steps does the escalator have?
两个顽皮的孩子逆着自动扶梯行驶的方向行走，男孩每秒可走3级，女孩每秒可走2级，结果从扶梯的一端到达另一端男孩走了80秒，女孩走了180秒，那么该扶梯共有多少级．
<gadget id="calculator">3 - 1.2</gadget>
<output>1.8</output>

<gadget id="calculator">80 * 1.8</gadget>
<output>144</output>

<result>144</result>