考點(diǎn):整數(shù)四則混合運(yùn)算,運(yùn)算定律與簡(jiǎn)便運(yùn)算
專(zhuān)題:運(yùn)算順序及法則,運(yùn)算定律及簡(jiǎn)算
分析:(1)(4)(5)根據(jù)分配律簡(jiǎn)算;
(2)(6)根據(jù)乘法交換律和結(jié)合律計(jì)算;
(3)根據(jù)商不變的性質(zhì)解答.
解答:
解:(1)28×111-28×11
=28×(111-11)
=28×100
=2800
(3)125×16×250
=(125×8)×(2×250)
=1000×500
=500000
(3)700÷25
=(700×4)÷(25×4)
=2800÷100
=28
(4)63×8+91×63+63
=63×(8+91+1)
=63×100
=6300
(5)93×99+93
=93×(99+1)
=93×100
=9300
(6)(25×19)×4
=19×(25×4)
=19×100
=1900
點(diǎn)評(píng):在四則運(yùn)算中,計(jì)算四則混合運(yùn)算時(shí),要按照運(yùn)算順序,先算乘除,后算加減,有括號(hào)的先算括號(hào)里面的,再算括號(hào)外面的.能簡(jiǎn)算的要簡(jiǎn)算.