(1)10-
8
9 ×
3
8 ÷
3
4 ,
=10-
1
3 ÷
3
4 ,
=10-
4
9 ,
=9
5
9 ;
(2)2-
5
11 -
6
11 ,
=2-(
5
11 +
6
11 ),
=2-1,
=1;
(3)
3
4 ×
5
7 -
3
4 ×
1
7 ,
=
3
4 ×(
5
7 -
1
7 ),
=
3
4 ×
4
7 ,
=
3
7 ;
(4)
1
4 ÷(3-
5
13 -
8
13 ),
=
1
4 ÷[3-(
5
13 +
8
13 )],
=
1
4 ÷[3-1],
=
1
4 ÷2,
=
1
8 .