问题
解答题
计算 (1)3.6-2.75+0.4-0.25 (2)0.75×
(3)2-
(4)2x-
(5)
|
答案
(1)3.6-2.75+0.4-0.25,
=3.6+0.4-(2.75+0.25),
=4-3,
=1;
(2)0.75×
+5 6
×3 4
,1 6
=0.75×(
+5 6
),1 6
=0.75×1,
=0.75;
(3)2-
÷6 13
-9 26
,2 3
=2-
×6 13
-26 9
,2 3
=2-(
+4 3
),2 3
=2-2,
=0;
(4)2x-
x=3 2
,4 5
x=1 2
,4 5
x×2=1 2
×2,4 5
x=1
;3 5
(5)
(2x-1)=1 2
,3 2
x-
=1 2
,3 2
x-
+1 2
=1 2
+3 2
,1 2
x=2.