The passenger car and the truck start from two places 630 kilometers apart at the same time, travel towards each other, and meet each other after 6 hours. It is known that the passenger car travels 48 kilometers per hour, how many kilometers per hour does the truck travel?
客车和货车同时从相距630千米的两地出发，相向而行，经6小时相遇．已知客车每小时行48千米，货车每小时行多少千米？
<gadget id="calculator">48 * 6</gadget>
<output>288</output>

<gadget id="calculator">630 - 288</gadget>
<output>342</output>

<gadget id="calculator">342 / 6</gadget>
<output>57</output>

<result>57</result>