Finding Z Value with Mass Spectra of Protein Fragments

[higherme]

I am given 2 mass spectra of protein fragments and don't get how to analysis a mass spectrum of a protein and find Z value with the given m/z ratios.

do i take the mass of the whole protein and divide by the m/z on the spectrum to find z?

thanks

 

[chemisttree]

No. Only the mass of the fragment responsible for the peak of interest.