反复应用运算定律、性质进行简算。如:
① 0.125×1.2×(12.7-2.3-2.4)
=0.125×1.2×〔12.7-(2.3+2.4)〕
=0.125×1.2×8
=0.125×8×1.2
=1.2
②1.4×98+3×1.4
=1.4×(98+3) (98+3=101=100+1)
=1.4×100+1.4
=140+1.4
=141.4
① 0.125×1.2×(12.7-2.3-2.4)
=0.125×1.2×〔12.7-(2.3+2.4)〕
=0.125×1.2×8
=0.125×8×1.2
=1.2
②1.4×98+3×1.4
=1.4×(98+3) (98+3=101=100+1)
=1.4×100+1.4
=140+1.4
=141.4