题目内容
计算: 91+85+87+106+115+94+113+101 | 123+119×2+121×3+120×4 | (1231+2312+3123)÷6 |
(12+23+34+45+56+61)÷7 | 34×77+34×23 | 42×37-42×17 |
28×32-28×17+28×84 | 26×14+26×8+22×4 | 132×31+18×24-7×132 |
92×49+108×51+92×51+49×108 | 127×42-58×38+74×58-42×91 | 11×13+22×8+33×7 |
123×36+246×17+3690 | 88×35-87×23-86×12 | 121×6+120×5+119×3-118×14 |
11×22+22×33+33×44+44×55+55×66 | 399÷7+91÷7 | 25÷4+25÷6+35÷4+35÷6 |
39÷7+62÷14 | 78÷17+83÷34+202÷68 | 75÷[9×6-3×(13+4)] |
12×[34×2+(34+5)×8]+34×80. |
考点:四则混合运算中的巧算
专题:计算问题(巧算速算)
分析:运用整数四则混合运算法则及其能简便的就简便进行计算即可.
解答:
解:①1+85+87+106+115+94+113+101
=(113+87)+(106+94)+(85+115)+(91+101)
=200×3+192
=792
②123+119×2+121×3+120×4
=120×10+4
=1200+4
=1204
③(1231+2312+3123)÷6
=6666÷6
=1111
④(12+23+34+45+56+61)÷7
=231÷7
=33
⑤34×77+34×23
=34×(77+23)
=34×100
=3400
(6)42×37-42×17
=42×(37-17)
=42×20
=840
(7)28×32-28×17+28×84
=28×(32-17+84)
=28×99
=28×(100-1)
=28×100-28
=2800-28
=2772
(8)26×14+26×8+22×4
=26×(14+8)+22×4
=22×(26+4)
=660
(9)132×31+18×24-7×132
=132×(31-7)+18×24
=24×(132+18)
=24×150
=3600
(10)92×49+108×51+92×51+49×108
=108×(51+49)+92×(49+51)
=100×(108+92)
=20000
(11)127×42-58×38+74×58-42×91
=(127-91)×42+58×(74-38)
=36×42+58×36
=36×(42+58)
=3600
(12)11×13+22×8+33×7
=11×13+11×16+11×21
=11×(13+16+21)
=11×50
=550
(13)123×36+246×17+3690
=123×(36+34)+3690
=8610+3690
=12200
(14)88×35-87×23-86×12
=86×(35-23-12)+2×35-23
=70-23
=47
(15)121×6+120×5+119×3-118×14
=118×(6+5+3-14)+3×6+2×5+3
=31
(16)11×22+22×33+33×44+44×55+55×66
=22×(11+33+66+110+165)
=22×385
=8470
(17)399÷7+91÷7
=(399+91)÷7
=490÷7
=70
(18)25÷4+25÷6+35÷4+35÷6
=(25+35)÷6+(25+35)÷4
=10+15
=25
(19)39÷7+62÷14
=78÷14+62÷14
=(78+62)÷14
=140÷14
=10
(20)78÷17+83÷34+202÷68
=312÷68+166÷68+202÷68
=(312+166+202)÷68
=680÷68
=10
(21)75÷[9×6-3×(13+4)]
=75÷[54-51]
=75÷3
=25
(22)12×[34×2+(34+5)×8]+34×80
=12×[68+39×8]+2720
=12×380+2720
=4560+2720
=7280
=(113+87)+(106+94)+(85+115)+(91+101)
=200×3+192
=792
②123+119×2+121×3+120×4
=120×10+4
=1200+4
=1204
③(1231+2312+3123)÷6
=6666÷6
=1111
④(12+23+34+45+56+61)÷7
=231÷7
=33
⑤34×77+34×23
=34×(77+23)
=34×100
=3400
(6)42×37-42×17
=42×(37-17)
=42×20
=840
(7)28×32-28×17+28×84
=28×(32-17+84)
=28×99
=28×(100-1)
=28×100-28
=2800-28
=2772
(8)26×14+26×8+22×4
=26×(14+8)+22×4
=22×(26+4)
=660
(9)132×31+18×24-7×132
=132×(31-7)+18×24
=24×(132+18)
=24×150
=3600
(10)92×49+108×51+92×51+49×108
=108×(51+49)+92×(49+51)
=100×(108+92)
=20000
(11)127×42-58×38+74×58-42×91
=(127-91)×42+58×(74-38)
=36×42+58×36
=36×(42+58)
=3600
(12)11×13+22×8+33×7
=11×13+11×16+11×21
=11×(13+16+21)
=11×50
=550
(13)123×36+246×17+3690
=123×(36+34)+3690
=8610+3690
=12200
(14)88×35-87×23-86×12
=86×(35-23-12)+2×35-23
=70-23
=47
(15)121×6+120×5+119×3-118×14
=118×(6+5+3-14)+3×6+2×5+3
=31
(16)11×22+22×33+33×44+44×55+55×66
=22×(11+33+66+110+165)
=22×385
=8470
(17)399÷7+91÷7
=(399+91)÷7
=490÷7
=70
(18)25÷4+25÷6+35÷4+35÷6
=(25+35)÷6+(25+35)÷4
=10+15
=25
(19)39÷7+62÷14
=78÷14+62÷14
=(78+62)÷14
=140÷14
=10
(20)78÷17+83÷34+202÷68
=312÷68+166÷68+202÷68
=(312+166+202)÷68
=680÷68
=10
(21)75÷[9×6-3×(13+4)]
=75÷[54-51]
=75÷3
=25
(22)12×[34×2+(34+5)×8]+34×80
=12×[68+39×8]+2720
=12×380+2720
=4560+2720
=7280
点评:考查了整数四则混合运算顺序,注意灵活运用验算定律进行简算.
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