问题
解答题
计算下面各题,能简便计算的要简算
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答案
(1)156×l0l-156
=156×(l0l-1)
=156×100
=15600
(2)404×25
=(400+4)×25
=400×25+4×25
=10000+100
=10100
(3)23×44+23×57-23
=23×(44+57-1)
=23×100
=2300
(4)99×38
=(100-1)×38
=100×38-38
=3800-38
=3762
(5)25×32×125
=25×4×8×125
=(25×4)×(8×125)
=100×1000
=100000
(6)400×[(270+80)÷7]
=400×[350÷7]
=400×50
=20000
(7)165+299
=165+(300-1)
=465-1
=464
(8)47×99+47
=47×(99+1)
=47×100
=4700
(9)630÷18÷5
=630÷(18×5)
=630÷90
=4
(10)(730-80÷2)÷23
=(730-40)÷23
=690÷23
=30
(11)525-20×5+25
=525-100+25
=(525+25)-100
=550-100
=450
(12)37+125+63+175
=(37+63)+(125+175)
=100+300
=400
(13)149×45-45×49
=(149-49)×45
=100×45
=4500
(14)1800÷25÷4
=1800÷(25×4)
=1800÷100
=18
(15)32×(50+4)
=32×50+4×32
=1600+128
=1728