问题
解答题
|
答案
①x+
=3 8
,9 8
x+
-3 8
=3 8
-9 8
,3 8
x=
;3 4
②x-
=3 7
,1 2
x-
+3 7
=3 7
+1 2
,3 7
x=
;13 14
③x÷2.5=0.8,
x÷2.5×2.5=0.8×2.5,
x=2;
④0.1x=30,
0.1x÷0.1=30÷0.1,
x=300.
|
①x+
=3 8
,9 8
x+
-3 8
=3 8
-9 8
,3 8
x=
;3 4
②x-
=3 7
,1 2
x-
+3 7
=3 7
+1 2
,3 7
x=
;13 14
③x÷2.5=0.8,
x÷2.5×2.5=0.8×2.5,
x=2;
④0.1x=30,
0.1x÷0.1=30÷0.1,
x=300.