What is the magnitude of the average force

The linear impulse delivered by the hit of a
boxer is 248 N · s during the 0.4 s of contact.
What is the magnitude of the average force
exerted on the glove by the other boxer?
Answer in units of N

Impulse = Average force x time so
Average force = impulse / time
= 248/0.4 = 620N

Using newtons 3rd law,the force exerted on the glove by the other boxer = -620N
(i.e. 620N in the opposite direction to the velocity of the 1st boxer's glove)

Impulse = Force * time

248 = Force * 0.4