7142.85÷3.7÷2.7×1.7×0.7
=7142.85×1.7×0.7÷3.7÷2.7
=793.65×9×(1.7×0.7÷3.7÷2.7)
=793.65×(9×17×7÷37÷27)
=264.55×(3×17×7÷37÷3)
=264.55÷37×17×7
=7.15×119
=(7+0.15)(120-1)
=840-7+18-0.15
=850.85
7142.85÷3.7÷2.7×1.7×0.7
=7142.85×1.7×0.7÷3.7÷2.7
=793.65×9×(1.7×0.7÷3.7÷2.7)
=793.65×(9×17×7÷37÷27)
=264.55×(3×17×7÷37÷3)
=264.55÷37×17×7
=7.15×119
=(7+0.15)(120-1)
=840-7+18-0.15
=850.85