Xiao Ming goes to his grandmother's house 1600 meters away, and runs 80 meters per minute. His puppy starts at the same time as him, and runs 250 meters per minute. When the dog arrived at the grandmother's house, it turned around and ran towards Xiao Ming, and when it met Xiao Ming, it turned around and ran towards the grandmother's house again, and kept going back and forth until Xiao Ming arrived at the grandmother's house. How much did the puppy run in total?
小明去1600米之外的外婆家，每分钟行80米，他的小狗和他同时出发，每分钟跑250米．这只狗到了外婆家后掉头向小明跑去，遇则小明后又掉头向外婆家跑去，这样不停地来回，直到小明到外婆家．这只小狗一共跑了多少路？
<gadget id="calculator">250 * 20</gadget>
<output>5_000</output>

<result>5_000</result>