Two people, A and B, are running on a 400-meter circular track. A runs 120 meters per minute, and B's speed is half as fast as A's. Now B is 100 meters in front of A, after how many minutes will they meet?
甲、乙两人比跑步，环形跑道为400米．甲每分钟跑120米，乙的速度比甲的速度多一半．现在乙在甲的前面100米，多少分钟后两人相遇？
<gadget id="calculator">400 - 100</gadget>
<output>300</output>

<gadget id="calculator">120 * 0.5</gadget>
<output>60</output>

<gadget id="calculator">300 / 60</gadget>
<output>5</output>

<result>5</result>