Chromium has four main isotopes.

50Cr, 52Cr, 53Cr, and 54CR

50Cr- 4.43% relative abundance 49.946 Isotopic Mass

52Cr- ? % relative abundance 51.941 Isotopic Mass

53Cr- ? % relative abundance 52.946 Isotopic Mass

54Cr- 2.28% relative abundance 53.939 Isotopic Mass

Average Mass = 51.996

Determine the two unkowns.... really stumped could use some help.

I know how to do the simple 65Cu, 63Cu with the 1-x but I just don't know how to put this one into an equation.

I suppose using two variables may be the key but I just don't know how to arrange it.

51.996= (51.941x)+((x-y)52.947)+(2.28*53.939)+(4.43*49.946)