The resultant value of ppm (parts per million) of CaCO3 in water samples X and Y would be the same, assuming that the difference in iron (III) ion concentration does not directly affect the concentration of dissolved calcium carbonate (CaCO3).
The ppm of CaCO3 refers to the concentration of calcium carbonate in a solution, typically measured as milligrams of CaCO3 per liter of water. This measurement is based solely on the concentration of CaCO3 and is not directly influenced by the presence or absence of other ions such as iron (III) ions.
Therefore, as long as the concentration of CaCO3 is identical in samples X and Y, the resultant value of ppm of CaCO3 will be the same, regardless of the difference in iron (III) ion concentration.