The express train travels 50 kilometers per hour, and the slow train travels 40 kilometers per hour. The slow train leaves for 2 hours before the express train passes from another place, and the two cars meet each other in 3 hours. How many kilometers are the distance between the two places?
快车每小时行50千米，慢车每小时行40千米，慢车先出发2小时，快车才从另一地方相对而行，3小时两车相遇．两地相距多少千米？
<gadget id="calculator">50 + 40</gadget>
<output>90</output>

<gadget id="calculator">90 * 3</gadget>
<output>270</output>

<gadget id="calculator">40 * 2</gadget>
<output>80</output>

<gadget id="calculator">270 + 80</gadget>
<output>350</output>

<result>350</result>