Seven minutes later, they are 860 meters apart, of which 300 meters is the distance from the gate. So in 7 minutes, Party A and Party B walked 860-300=560 meters.

Solution: Let B walk x meters every minute.

(37+X)*7=860-300

259+7X=560

7X=30 1

X=43

A: B walks 43 meters per minute.