PHYSICAL SCIENCE
posted by JACQUELYNNE .
A 30 KG GIRL AND A 25 KG BOY FACE EACH OTHER ON FRICTIONFREE ROLLER BLADES. THE GIRL PUSHES THE BOY, WHO MOVES AWAY AT A SPEED OF 1.0 M/S. THE GIRLS SPEED IS?

The boys change of momentum is equal and opposite to the girls change of momentum.
GirlMomentum=Boy momentum
30kg*V=25kg*1.0m/s 
0.83