What does it mean by " concentrations are (value) in relation to each other"? This is not a home work help question or something like that, these days I self learn chemistry and when I was doing a model paper I came across this question. And the question itself is not difficult but I don't understand this term.

More accurately, I am not familiar with this term, 
 
that part of the question says, 


  The cation Ag+(aq) and Hg2^2+ are in an aquesous solution.Their concentrations are 0.2 moldm-3 in relation to each other. Find which cation precipitates first as its iodide when a solution of NaI is added gradually to the above solution... and there are some other sub questions,
  


If you can explain to me if what it means by "Their concentrations are 0.2 moldm-3 in relation to each other", I think I can do the question easily, Thank you!
The cation Ag+(aq) and Hg2^2+ are in an aqueous solution. Their
  concentrations are 0.2 moldm^-3 in relation to each other. Find which
  cation precipitates first as its iodide when a solution of NaI is
  added gradually to the above solution


It is a poorly worded question. The author means that the ratio of Ag conc. to Hg conc. is 0.2. It is implied that the concentration of silver is lower. Which ion will ppt out first, if we add NaI?

The author should have written that the relative ratio of Ag:Hg concentration is 0.2.