Several mathematical errors in the published paper by Zhao and co-workers are identified. The errors pertain to the calculated equation coefficients for the polynomial version of the combined nearly ideal binary solvent (CNIBS)/Redich-Kister and for the Combined Jouyban–Acree–van’t Hoff equation. In the case of the CNIBS/Redlich–Kister equation the authors’ tabulated equation coefficients give 100 times the mole fraction solubility of olaparib, and not the mole fraction solubility as the authors’ equation implies.