If I understand you correctly:
Now we know the individual amount of stocksolution you were taken, but we don’t know the individual end volume of each sample.
Without you are not able to calculate the final concentration of each sample.
If I assume that the end volume was always the same the final concentration ratio must follow the used volume of the stocksolution.
Not sure what you mean by end volume of each sample.
All I did was titrate 1 mL of stock solution, then 2, then 3, then 4, then 5. Added 20 mL of NH3 to all of those and then filled the remainder up with DI water to 100 mL mark. But don't think that's necessary to know.
When I make my graph, I will have the absorbance on the y axis. The concentration of the known on the X. When I draw a straight line, I can then look at the absorbance and line it up with the concentration axis to get the concentration, then I just do M1V1 = M2V2 to get the concentration after diluted.
Erm....I think maybe I know what you're talking about. That 100 mL actually was important wasn't it?
.125 X volume of stock solution divided by 100 mL = concentration
Is that right?