Question

【題目】計(jì)算下列各題，能簡(jiǎn)算的要簡(jiǎn)算
① ×6﹣4÷
②7.2﹣4.28+2.8﹣0.72
③53.4÷[1÷（3.1﹣3.09）]
④ ÷ ﹣ ×
⑤ ÷[（ + ）÷15]
⑥36×0.71+3.6×2.9．

Answer 1

【答案】解：① ×6﹣4÷
= ×6﹣4×
=（6﹣4）×
=2×
= ；
②7.2﹣4.28+2.8﹣0.72
=（7.2+2.8）﹣（4.28+0.72）
=10﹣5
=5；
③53.4÷[1÷（3.1﹣3.09）]
=53.4÷[1÷0.01]
=53.4÷100
=0.534；
④ ÷ ﹣ ×
= × ﹣ ×
= ﹣
= ；
⑤ ÷[（ + ）÷15]
= ÷[ ÷15]
= ÷ ÷15
= ×
= ；
⑥36×0.71+3.6×2.9
=3.6×7.1+3.6×2.9
=3.6×（7.1+3.9）
=3.6×10
=36．
【解析】①把除法變成乘法，再根據(jù)乘法分配律進(jìn)行計(jì)算即可；②根據(jù)加法交換律和減法的性質(zhì)進(jìn)行計(jì)算即可；③先算小括號(hào)里的減法，再算中括號(hào)里的除法，最后算括號(hào)外的除法；④先算除法和乘法，再算減法；⑤先算小括號(hào)里的加法，再按照從左到右的順序計(jì)算即可；⑥根據(jù)乘法分配律進(jìn)行計(jì)算即可．