用递等式计算. 68×35-408÷24 8/49÷[9/8-(1/8+3/7)] 18-10.4÷(6.2-4.9)

问题描述:

用递等式计算.

68×35-408÷24
8
49
÷[
9
8
-(
1
8
+
3
7
)]
18-10.4÷(6.2-4.9)

(1)68×35-408÷24,
=2380-17,
=2363;
(2)

8
49
÷[
9
8
-(
1
8
+
3
7
)],
=
8
49
÷[
9
8
-
1
8
-
3
7
],
=
8
49
÷[1-
3
7
],
=
8
49
×
7
4

=
2
7

(3)18-10.4÷(6.2-4.9),
=18-10.4÷1.3,
=18-8,
=10.