Xiaoming and Xiaodong set out from two places 5500 meters apart at the same time. Xiaoming walks 60 meters per minute, Xiaodong walks 50 meters per minute, Xiaoming brings a dog, each dog.

Suppose it takes t minutes for two people to meet.

(60+50)t=5500,

? 1 10t=5500,

t = 50

So the distance the puppy runs is:

250×50= 12500 (m),

12500m = 12.5km;

A: The dog ran away 12.5 km.