Twenty Hong Kong Chinese undergraduate students were recruited to examine t
he patterns of the odd-even effect observed in Lemaire and Fayol (1995). In
the present study, the odd-even effect was found only in difficult problem
s for which problems and answers were presented simultaneously. Since parti
cipants in the present study were believed to possess faster retrieval spee
d than those in Lemaire and Fayol (1995), the results suggest that memory r
etrieval and parity-checking are executed in parallel, and are consistent w
ith the multiple-strategy hypothesis which states that there is a horse rac
e between the fact retrieval and parity-checking processes during verificat
ion. Implications about the superiority of Chinese in solving simple arithm
etic are also discussed.