问题补充说明：求大家了，我很急，答案最好带上
1来自. 67 ×21 ＋18 ×21 + 85 ×79
=21×(67+18)+85×79
=21×85+85×79
=85×(21+360问答79)
=8500
2. 3军何配物状流协75 ×480 + 6250 ×48
=480×(375＋625)
=480000
3. 321 ×81 + 321 ×19
=321×(81+19)
=32100
4. 222缩零电等律体222 ×999999
=222222×(1000000－1)
=222222000000－222222
=222221777778
5. 333333 ×333333
=111111×999999
=111111×(1000000－1)
=11111100降检让0000－111111
=111110888889
球求套护6. 654321 ×909090 +654321×90909
=654321×9向走穿宗板听地班区织信99999
=654321×(100000－1)
=654321000000－654321
=654320345679
7. 34 ×3535 －35 ×3434
=34×35×101－35×34×101
=0
8. 345345 ÷15015
=345×1001÷(15×1001)
=345÷15×1001÷1001
=23
9. 75 ×45 + 17 ×25
=25×3×置45+17×25
=25×(135+17)
=25×152
=25×4×38
=3800
10. （4纪间波厂医车效期8 ×75 ×81族配袁更随甚称赶味红）÷（24 ×25 ×27）
=48÷24×75÷25×81÷27
=2×3×3
=18
1. 125 ×（17 ×8）×4
= 125×8×4×17
=1000×68
=68000
2. 25 ×16 ×125
=25×2×8×125
=50000
3. 75000 ÷125 ÷15
=75×1000÷125÷15
=75÷15×1000÷125
=5×步我耐圆失8
=40
4. 150 ×40 ÷50
=150÷50×40
=3×40
=120
5. 7900 ÷4 ÷25
=7900÷(4×2板贵西距5)
=79
6. 27000 ÷125
=27×1000÷125
=27×8
=216
7. 210 ÷42 ×6
=秋量血创更金矛钟210÷7÷6×6
=30
8. 56000 ÷ （14000 ÷16）
=4×16
=64
9. 5600 ÷（25 ×7）
=56×100÷25÷7
=56÷7×100÷25
=32
10. 13 ×99
=13×(100－确相只病1)
=1300－13
=1287
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标签：下册,四年级
