2x8.1+11x9.25+537x0.

41.2x8.1+11x9.25+537x0.19=41.2x8.1+11x9.25+53.7x1.9=41.2x8.1+11x（8＋1.25）+（41.2＋12.5）x1.9=41.2×8.1＋41.2×1.9＋11×8＋11×1.25＋12.5×1.9=41.2×（8.1＋1.9）＋11×8＋11×1.25＋1.25×19=41.2×10＋...