Xiao Pang and Xiao Ding Ding went from school to Shanghai Museum of Natural History. Xiao Pang ran 400 meters first, and then Xiao Ding Ding set off to catch up with Xiao Pang along the same route. How many meters run per minute on average?
小胖和小丁丁从学校去上海自然博物馆，小胖先跑400米后小丁丁沿同一路线出发追赶小胖，小丁丁平均每分钟跑160米，四分钟后在途中追上小胖，小胖平均每分钟跑多少米？
<gadget id="calculator">160 * 4</gadget>
<output>640</output>

<gadget id="calculator">640 - 400</gadget>
<output>240</output>

<gadget id="calculator">240 / 4</gadget>
<output>60</output>

<result>60</result>