The distance between A and B is 490 kilometers. The truck leaves from A at a speed of 50 km/h. After 1 o'clock, the bus leaves from B. After 4 hours, the bus meets the truck. How many kilometers does the bus travel per hour?
甲、乙两地相距490千米，货车从甲地开出，速度是50千米/时，1时后，客车从乙地开出，客车行驶4时后与货车相遇．客车每时行驶多少千米？
<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">50 * 5</gadget>
<output>250</output>

<gadget id="calculator">490 - 250</gadget>
<output>240</output>

<gadget id="calculator">240 / 4</gadget>
<output>60</output>

<result>60</result>