# Question #9206b

For Manganese-60, X = Mn (from the periodic table), A = 60 (given in the problem), and Z = 25 (from the periodic table). The isotopic notation for Manganese-60 is $\text{_25^60 "Mn}$.
If you are asked to calculate the number of neutrons, simply subtract Z from A. For $\text{_25^60 "Mn}$, the number of neutrons, N, is 60 - 25 = 35.