几个简便计算,哥哥姐姐们,速求,(1)9*17+91/17-5*17+45/17(2)51*49+3.15*49+51*3.15(3)1234+3142+4321+2413(4)123+234+345+456+567+678+789
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![几个简便计算,哥哥姐姐们,速求,(1)9*17+91/17-5*17+45/17(2)51*49+3.15*49+51*3.15(3)1234+3142+4321+2413(4)123+234+345+456+567+678+789](/uploads/image/z/2998825-25-5.jpg?t=%E5%87%A0%E4%B8%AA%E7%AE%80%E4%BE%BF%E8%AE%A1%E7%AE%97%2C%E5%93%A5%E5%93%A5%E5%A7%90%E5%A7%90%E4%BB%AC%2C%E9%80%9F%E6%B1%82%2C%EF%BC%881%EF%BC%899%2A17%2B91%2F17-5%2A17%2B45%2F17%EF%BC%882%EF%BC%8951%2A49%2B3.15%2A49%2B51%2A3.15%EF%BC%883%EF%BC%891234%2B3142%2B4321%2B2413%EF%BC%884%EF%BC%89123%2B234%2B345%2B456%2B567%2B678%2B789)
几个简便计算,哥哥姐姐们,速求,(1)9*17+91/17-5*17+45/17(2)51*49+3.15*49+51*3.15(3)1234+3142+4321+2413(4)123+234+345+456+567+678+789
几个简便计算,哥哥姐姐们,速求,
(1)9*17+91/17-5*17+45/17
(2)51*49+3.15*49+51*3.15
(3)1234+3142+4321+2413
(4)123+234+345+456+567+678+789
几个简便计算,哥哥姐姐们,速求,(1)9*17+91/17-5*17+45/17(2)51*49+3.15*49+51*3.15(3)1234+3142+4321+2413(4)123+234+345+456+567+678+789
(1)9*17+91/17-5*17+45/17
=(9-5)*17+(91+45)/17
=4*17+8
=38+8
=76
(2)51*49+3.15*49+51*3.15
=51*(50-1)+3.15*(49+51)
=51*50-51+3.15*100
=2550-51+315
=2814
(3)1234+3142+4321+2413
=1111×(12+3+4)
=1111×10
=11110
(4)123+234+345+456+567+678+789
=(1+2+3+4+5+6+7)×100+(2+3+4+5+6+7+8)×10+3+4+5+6+7+8+9
=28×100+35×10+42
=2800+350+42
=3192
1.=9*17+91/17-5*17+45/17=(9-5)*17+1/17(91+45)
2.
3.=(1234+4321)*2
4.=(123+789)*3+456
76
2814
11110
3192
(1)9*17+91/17-5*17+45/17=17(9-5)+(91+45)/17=68+8=76
(2)51*49+3.15*49+51*3.15=51*49+3.15(49+51)=(50+1)(50-1)+315=2500-1+315=2814
(3)1234+3142+4321+2413=11110 用竖式算
(4)123+234+345+456+567+678+789=3192 用竖式算再结合 3+4+5+6+7+8+9=6*7=42等巧算
1)原式=17*(9-5)+(91+45)/17=17*4+8=76
2)原式=50*50-50+49+3.15*(49+51)=2813
3)原式=(1+2+3+4)*1111=11110
4)原式=((123+789)*7)/2=456*7=3192