Speed of proton and alpha particle

[colmes]

Homework Statement

An alpha particle (4 times the mass of a proton with a charge of +2e) is at rest 1.0 * 10^-12 m from a stationary proton. The 2 particles immediately move apart. Find the speed of each particle when they are infinitely far from each other.

Homework Equations

Electrical Energy = kq1q2/r
Kinetic Energy = 0.5mv^2

The Attempt at a Solution

I used the equation kq1q2/r to find the potential energy of the system and converted the potential energy into 0.5mv^2 to solve for the velocity. I am not sure that I have the right answer.

 

[lightgrav]

right approach ... but which one is moving faster? how many times as fast is it?
what fraction of the total KE does the fast one have?