2·4
-
5
=
30
-
5·4
=
10
13
+
(
2
-
3
)
·
(
8
-
2
)
=
7
(
55
:
5
-
1
)
:
2
=
5
10
-
:
6
=
5
-
15
=
1
(
7·7
-
7
)
:
7
+
4
=
10
2
-
5
-
(
-
3
)
=
3
3
+
:
9
-
10
=
2
[
25
-
5·
(
2
-
3
)
]
:
5
=
6