简便计算40加450除18 0.24除[1.6乘(2减1.5)] 7分之4加7分之3乘6分之5 12乘(4分之1加13分

①40+450÷18
=40+50÷2
=40+25
=65
②0.24÷[1.6×﹙2-1.5﹚]
=0.24÷﹙1.6×0.5﹚
=0.24÷1.6÷0.5
=0.06÷0.4÷0.5
=3÷20÷0.5
=0.15÷0.5
=15÷50
=3÷10
=0.3
③4/7+3/7×5/6
=4/7+5/14
=8/14+5/14
=13/14
④12×﹙1/4+1/13)×26
=12×[﹙1/4+1/13)×26]
=12×﹙13/2+2﹚
=78+24
=102
⑤7/9÷11/5＋5/11×2/9
=7/9×5/11＋5/11×2/9
=﹙7/9+2/9﹚×5/11
=1×5/11
=5/11

40加450除18
=40+50×9÷18
=40+50÷2
=40+25
=65

0.24除[1.6乘(2减1.5)]
=0.24÷（1.6x0.5）
=0.24÷0.8
=0.3

7分之4加7分之3乘6分之5
=4/7+（3 x5/6）/7
=（4+5/2) /7

您好：

40加450除18
=40+25
=65

0.24除[1.6乘(2减1.5)]
=0.24÷（1.6x0.5）
=0.24÷0.8
=0.3

7分之4加7分之3乘6分之5
=1/7x4+1/7x5/2
=1/7x(4+5/2)
=1/7x13/2
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