Car B is traveling in front of car A at the same speed. If the speed of car A is 65 km/h, it can catch up with car B in 5 hours; if the speed of car A is 75 km/h, then it can catch up with car B in 3 hours. How many kilometers does car B travel per hour?
乙车以相同的速度在甲车前面行驶．如果甲车速度是65千米/小时，5小时就可以追上乙车；如果速度是75千米/小时，那么3小时就可以追上乙车．乙车每小时走多少千米？
<gadget id="calculator">65 * 5</gadget>
<output>325</output>

<gadget id="calculator">75 * 3</gadget>
<output>225</output>

<gadget id="calculator">325 - 225</gadget>
<output>100</output>

<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">100 / 2</gadget>
<output>50</output>

<result>50</result>