(6+4)x= 100

10x= 100

The solution is x= 10.

(2) According to the meaning of the question, the running time of the puppy is just the time from A to B, that is, 10 hour, and:

10× 10= 100 (plum)

A: After 10 hour, Party A and Party B met and the dog ran away 100 mile.