9.8×65.2×1.25-12.5×0.65×18=98×6.52×1.25-1.25×6.5×18=98×(6.5+0.02)×1.25-1.25×6.5×18=98×1.25×6.5+98×0.02×1.25-1.25×6.5×18=1.25×6.5×(98-18)+98×0.02×1.25=1.25×6.5×80+98×0.02×1.25=650+2.45=652.45
