No clue on this one

A 55.0 kg high school baseball pitcher is holding a 149 g baseball as he slides horizontally on a frictionless surface with a velocity of +2.15 m/s, relative to the surface. He then throws the baseball with a velocity of +46.7 m/s relative to the surface....

so do you plug the value in for the velocity of the man or no. either way this is too big of a number. The answer is 2.01 but I can't get that?

I really need help with this question please