考點(diǎn):運(yùn)算定律與簡便運(yùn)算
專題:運(yùn)算定律及簡算
分析:(1)4.4=1.1×4,然后根據(jù)乘法交換律和結(jié)合律,計(jì)算即可;
(2)125×0.08=12.5×0.8,然后根據(jù)乘法分配律計(jì)算即可;
(3)1.6=4×0.4,然后根據(jù)乘法交換律和結(jié)合律,計(jì)算即可;
(4)4.8=8×0.6,然后根據(jù)乘法結(jié)合律,計(jì)算即可;
(5)4.8=8×0.6,然后根據(jù)乘法結(jié)合律和交換律,計(jì)算即可;
(6)100.1=100+0.1,然后根據(jù)乘法分配律,計(jì)算即可;
(7)0.37×872=3.7×87.2,然后根據(jù)然后根據(jù)乘法分配律,計(jì)算即可;
(8)16=8×2,然后根據(jù)乘法交換律和結(jié)合律,計(jì)算即可;
(9)8.8=1.1×8,然后根據(jù)乘法交換律和結(jié)合律,計(jì)算即可;
(10)根據(jù)乘法分配律,展開,計(jì)算即可;
(11)0.24×8.1=2.4×0.81,然后根據(jù)乘法分配律,計(jì)算即可;
(12)105=100+5,然后根據(jù)乘法分配律,展開,計(jì)算即可;
(13)根據(jù)乘法分配律,提取4.6,計(jì)算即可;
(14)3.7×830=37×83,然后根據(jù)乘法分配律,計(jì)算即可;
(15)根據(jù)乘法分配律,提取0.6,計(jì)算即可.
解答:
解:(1)4.4×2.5
=(1.1×4)×2.5
=1.1×(4×2.5)
=1.1×10
=11
(2)12.5×0.2+125×0.08
=12.5×0.2+12.5×0.8
=12.5×(0.2+0.8)
=12.5×1
=12.5
(3)1.6×2.5
=(0.4×4)×2.5
=0.4×(4×2.5)
=0.4×10
=4
(4)12.5×4.8
=12.5×(8×0.6)
=(12.5×8)×0.6
=100×0.6
=60
(5)12.5×3.2×4.8
=12.5×3.2×(0.6×8)
=(12.5×8)×(3.2×0.6)
=100×1.92
=192
(6)4.82×100.1
=4.82×(100+0.1)
=4.82×100+4.82×0.1
=482+0.482
=482.482
(7)3.7×12.8+0.37×872
=3.7×12.8+3.7×87.2
=3.7×(12.8+87.2)
=3.7×100
=370
(8)12.5×16
=12.5×(8×2)
=(12.5×8)×2
=100×2
=200
(9)8.8×12.5
=(1.1×8)×12.5
=1.1×(8×12.5)
=1.1×100
=110
(10)0.8×(12.5+1.25)
=0.8×12.5+0.8×1.25
=10+1
=11
(11)2.4×0.19+0.24×8.1
=2.4×0.19+2.4×0.81
=2.4×(0.19+0.81)
=2.4×1
=2.4
(12)3.6×105
=3.6×(100+5)
=3.6×100+3.6×5
=360+18
=378
(13)4.6-0.9×4.6
=4.6×(1-0.9)
=4.6×0.1
=0.46
(14)3.7×830+83×63
=37×83+83×63
=83×(37+63)
=83×100
=8300
(15)3.7×0.6+5.3×0.6
=0.6×(3.7+5.3)
=0.6×9
=5.4
點(diǎn)評:完成本題要注意分析式中數(shù)據(jù),運(yùn)用合適的簡便方法計(jì)算.