题目内容
(每小题4分,共16分)
(1) (2)
(3)(2-4-1)×(-) (4)
(1) (2)
(3)(2-4-1)×(-) (4)
(1)20,(2)4.5,(3)3,(4)-79
解:(1)原式=(-7-6)+13+20
=-13+13+20
=(-13+13)+20
=20
(2)原式=
=
=
=4.5
(3)原式=
=
=
=3
(4)原式
=-13+13+20
=(-13+13)+20
=20
(2)原式=
=
=
=4.5
(3)原式=
=
=
=3
(4)原式
练习册系列答案
相关题目