Chemical equation and calculation for remineralization system

Dear all, I am designing a remineralization system(Lime and CO2 gas injection to BWRO permeate ). So, our company received consultant from a vendor. Below chemical equation and calculation had calculated from a  vendor. However, we don't know how to calculate below data "As such required: 39.22, 46.64, 85.86", "Actual alkalinity produced: 47.567, 87.5675". If you know well chemical equations and this calculation, please let me know how to calculate. Thank you.      Dose Calculation for Lime + CO2                                                     Ca(OH)2 + 2CO2 = Ca(HCO3)2                                                           74           88            162 As such required:                         39.22      46.64        85.86 As CaCO3:                                        53           53              53 Dosages as Such provided:           40           50          92.045 Actual alkalinity produced:                        47.567      87.5675