Zhang Yuan and Li Xin are classmates and live in the same building with the same door number. Li Xin went home from school at a speed of 80 meters per minute. After walking 2,400 meters, Zhang Yuan rode a bicycle along Li Xin's home route at a speed of 240 meters per minute. How many minutes can Zhang Yuan catch up with Li Xin?
张元和李欣是同班同学，并住在同一幢楼的同一个门号里．李欣以每分钟80米的速度先从学校回家，走了2400米后，张元骑自行车沿李欣回家的路线以每分钟240米的速度也回家．张元多少分钟能追上李欣？
<gadget id="calculator">240 - 80</gadget>
<output>160</output>

<gadget id="calculator">2_400 / 160</gadget>
<output>15</output>

<result>15</result>