用简便方法计算.7-117-37(23-16-18)×4879×813+79÷135.-数学

题文

用简便方法计算.
7-
11
7
-
3
7
2
3
-
1
6
-
1
8
)×48
7
9
×
8
13
+
7
9
÷
13
5
题型:解答题  难度:中档

答案

(1)7-
11
7
-
3
7

=7-(
11
7
+
3
7
),
=7-2,
=5;

(2)(
2
3
-
1
6
-
1
8
)×48,
=
2
3
×48-
1
6
×48-
1
8
×48,
=32-8-6,
=18;

(3)
7
9
×
8
13
+
7
9
÷
13
5

=
7
9
×
8
13
+
7
9
×
5
13

=
7
9