There is a road 217.5 kilometers long between the east and the west. Car A travels from east to west at a speed of 25 kilometers per hour. After 1.5 hours, car B starts from the west. After another 3 hours, the distance between the two cars is still 15 kilometers. , how many kilometers does car B travel per hour?
东西两地间有一条公路长217.5千米，甲车以每小时25千米的速度从东到西地，1.5小时后，乙车从西地出发，再经过3小时两车还相距15千米，乙车每小时行多少千米？
<gadget id="calculator">25 * 1.5</gadget>
<output>37.5</output>

<gadget id="calculator">217.5 - 37.5 - 15</gadget>
<output>165</output>

<gadget id="calculator">165 / 3</gadget>
<output>55</output>

<gadget id="calculator">55 - 25</gadget>
<output>30</output>

<result>30</result>