Two cars set off from A and B at the same time and drive toward each other. After 3.2 hours, the two cars meet at a distance of 8 km from the midpoint. The fast train travels 45 km per hour, how many kilometers per hour does the slow train travel?
两车从甲、乙两地同时出发，相向而行，3.2小时后两车在距中点8km处相遇．快车每小时行45km，慢车每小时行多少千米？
<gadget id="calculator">2 / 3.2</gadget>
<output>0.625</output>

<gadget id="calculator">8 * 0.625</gadget>
<output>5</output>

<gadget id="calculator">45 - 5</gadget>
<output>40</output>

<result>40</result>