Tiantian and Mingming run along a 400-meter circular track. They start from the same point at the same time and walk in the same direction. They run 240 meters per minute every day, and Mingming runs 200 meters per minute. Obviously side by side?
天天、明明两人沿着400米的环形跑道跑步，他们同时从同一点出发，同向而行，天天每分跑240米，明明每分跑200米，起跑后经过多少分天天第二次和明明并肩？
<gadget id="calculator">240 - 200</gadget>
<output>40</output>

<gadget id="calculator">2 / 40</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">400 * (1/20)</gadget>
<output>20</output>

<result>20</result>