A92-kg rugby player running at 7.5 m/s collides in midair with a 112-kg player moving in the opposite direction. after the collision each player has zero velocity.

what was the initial speed of the 112-kg player before the collision?

By the condition of momentum conservation we can say that since there is no external force along horizontal direction so we will have

here we know that

also we know that

now from above equation we have

now we have

so the speed of the other player must be 6.16 m/s

the answer is 3.1 his answer is wrong mines is right