A train departs from Shanghai to Beijing and travels an average of 128 kilometers per hour. At the same time, another train departs from Beijing to Shanghai and travels an average of 80 kilometers per hour. The two trains meet after 7 hours. Find the distance between Beijing and Shanghai How many kilometers is the railway?
一列火车从上海出发到北京，平均每小时行128千米，与此同时，另一列火车从北京出发到上海，平均每小时行80千米，两列火车7小时后相遇，求北京到上海的铁路长多少千米？
<gadget id="calculator">128 + 80</gadget>
<output>208</output>

<gadget id="calculator">208 * 7</gadget>
<output>1_456</output>

<result>1_456</result>