A and B run along a 400-meter circular track. A's speed is three-fifths of B's speed. They start from the same point on the runway at the same time and run in the opposite direction. After 200 seconds, they met for the fourth time. How many meters per second is B's speed faster than A's speed?
A与B沿着400米的圆形跑道跑步．A的速度是B速度的五分之三．他们同时从跑道上的同一点出发逆向而跑．200秒钟之后，他们第四次相遇．B的速度比A的速度每秒钟快多少米．
<gadget id="calculator">4 / 200</gadget>
<output>1/50 = around 0.02</output>

<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">400 * (1/50) * (3/8)</gadget>
<output>3</output>

<gadget id="calculator">8 - 3 - 3</gadget>
<output>2</output>

<result>2</result>