用递等式计算,能简算的简算:85×54÷18+7453.4÷[(1.25+0.45)×23]35×(1-37)÷512(156×413-26)×81178×1213+78÷1385.87-(5.87+2.9)-数学
题文
用递等式计算,能简算的简算:
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答案
(1)85×54÷18+745, =85×(54÷18)+745, =85×3+745, =255+745, =1000; (2)3.4÷[(1.25+0.45)×23], =3.4÷[1.7×23], =3.4÷1.7÷23, =2÷23, =
(3)35×(1-
=35×
=35×
=48; (4)(156×
=(48-26)×
=22×
=16; (5)
= |