The total length of the road to Zunyi is 270 kilometers. Two cars drive from two cities at the same time. After 1.8 hours, they meet each other. Car A travels 72 kilometers per hour. What is the speed of car B?
到遵义的公路全长270千米，两辆汽车分别从两城同时相对开出，经过1.8小时相遇，甲车每小时行驶72千米，乙车的速度是多少？
<gadget id="calculator">270 / 1.8</gadget>
<output>150</output>

<gadget id="calculator">150 - 72</gadget>
<output>78</output>

<result>78</result>