What is the Velocity of Object A After an Inelastic Collision?

[nlsherrill]

Homework Statement

Object A, which has a mass m and a velocity v0i, collides head-on with object B, which has a mass 2m and a velocity 1/2v0j. Following the collision, object B has a velocity of 1/4v0i.

-Find the velocity of object A after the collision.

-Express the change in kinetic energy in terms of m and v0

Homework Equations

The Attempt at a Solution

I got 1/2i+j for the velocity and I am not sure why it is wrong. I set up the conservation of momentum equation and canceled the "m"s and just multiplied the coefficients(1 and 2) times the number in front of the velocity(either 1, 1/2, or 1/4) if that makes any sense.

 

[nlsherrill]

bump.

anyone? It doesn't seem difficult at all. I don't know what I'm missing here..