My textbook says the binding energy per nucleon is the energy needed to remove one nucleon from the nucleus, In a subsequent numerical which is as follows "The binding energy per nucleon for C12 is 7.68 MeV and that for C13 is 7.47 MeV. Calculate the energy required to remove a neutron from C13".The solution given is-"13 X 7.47 - 12 X 7.68 = 4.95 MeV".
The Attempt at a Solution
According to the definition provided of binding energy per nucleon the answer should be just 7.47 MeV, instead they calculated the Q value- Why did they do that and what blunder am I making? I'd really appreciate your help, thank you.