On weekends, Xia Wei borrowed books from classmate Liu Xing. Enthusiastic Liu Xing knew that Xia Wei was coming in the scorching heat, so he rode a bicycle to pick him up immediately. It is known that the distance between the two is 3200 meters. They set off at the same time, Xia Wei walked 70 meters per minute, and they met after 10 minutes. How many meters does Liu Xing travel on average per minute?
周末，夏威向同学刘星借书．热心的刘星知道夏威冒酷暑而来，马上骑自行车去接他．已知两家相距3200米．他俩同时出发，夏威每分钟走70米，10分钟后两人相遇．刘星平均每分钟行多少米？
<gadget id="calculator">3_200 / 10</gadget>
<output>320</output>

<gadget id="calculator">320 - 70</gadget>
<output>250</output>

<result>250</result>