Xiao Gang and Xiao Qiang set off from opposite sides at the same point on the 400-meter circular runway, and they met for the first time 40 seconds after departure. It is known that Xiaogang runs 4.5 meters per second, how many meters does Xiaoqiang run per second?
小刚和小强在400米的环形跑道上，从同一地点相背出发，出发后40秒两人第一次相遇．已知小刚每秒跑4.5米，求小强每秒跑多少米．
<gadget id="calculator">400 / 40</gadget>
<output>10</output>

<gadget id="calculator">10 - 4.5</gadget>
<output>5.5</output>

<result>5.5</result>