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计算(要灵活使用运算律哟).×+÷=;7.28-3.14+1.72-2.86=;(+-)×36=;[(5-4.75)÷1+2.7]×0.4=.

题目详情
计算(要灵活使用运算律哟).
×+÷=________;
7.28-3.14+1.72-2.86=________;
+-)×36=________;
[(5-4.75)÷1+2.7]×0.4=________.
▼优质解答
答案和解析
    3    1    1.18
(1)×+÷
=×+×
=(+)×
=1×
=
(2)7.28-3.14+1.72-2.86,
=(7.28+1.72)-(3.14+2.86),
=9-6,
=3;
(3)(+-)×36,
=×36+×36-×36,
=3+4-6,
=1;
(4)[(5-4.75)÷1+2.7]×0.4,
=[0.25÷1+2.7]×0.4,
=[0.25+2.7]×0.4,
=0.25×0.4+2.7×0.4,
=0.1+1.08,
=1.18.
故答案为:,3,1,1.18.