计算下面各题. 78-213+18 23+16-19 1-15-15 79-(15-110

计算下面各题. 78-213+18 23+16-19 1-15-15 79-(15-110)
2025-05-18 20:52:19
推荐回答(1个)
回答(1):

(1)

7
8
-
2
13
+
1
8

=
7
8
+
1
8
?
2
13

=1-
2
13

=
11
13


(2)
2
3
+
1
6
-
1
9

=
12
18
+
3
18
?
2
18

=
13
18


(3)1-
1
5
-
1
5

=1-(
1
5
+
1
5
),
=1-
2
5

=
3
5


(4)
7
9
-(
1
5
-
1
10
),
=
7
9
-(
2
10
-
1
10
),
=
7
9
?
1
10

=
61
90