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Calculate the number of neutrons present in the nucleus of an element X which is represented \(_{15}\textrm{X}^{31}\).
  
Given element is \(_{15}\textrm{X}^{31}\).
Atomic number \(=\)
Mass number \(=\)
We know,
Atomic number \(=\) Number of \(=\) Number of electrons
Number of neutrons \(=\) .