用你喜欢的方法计算下列各题．27-18+43-22；129×97+129×4-129；72×[（78+15）÷0.4]；24×5143+51×1943．

Question

用你喜欢的方法计算下列各题．
27-18+43-22；                           129×97+129×4-129；
72×[（78+(1)/(5)）÷0.4]；                     24×(51)/(43)+51×(19)/(43)．

Answer 1

（1）27-18+43-22
=27+43-（22+18）
=70-40
=30

（2）129×97+129×4-129
=129×（97+4-1）
=129×100
=12900

（3）72×[（78+(1)/(5)）÷0.4]
=72×[78.2÷0.4]
=72×195.5
=14076

（4）24×(51)/(43)+51×(19)/(43)
=24×(51)/(43)+19×(51)/(43)
=（24+19）×(51)/(43)
=43×(51)/(43)
=51