Answer
A neutron-rich nuclide decays by beta (minus) decay. A neutron-poor nuclide undergoes positron decay or electron capture.
Work Step by Step
Things to remember when solving this problem.
Neutrons decay to create beta (minus) particles. Therefore, neutron-rich nuclides undergo beta (minus) decay.
Protons decay to create positron particles. Therefore, proton-rich nuclides undergo positron decay.