(1)
5
4 ×
1
2 ×
3
5 ,
=
5
4 ×
3
5 ×
1
2 ,
=
3
4 ×
1
2 ,
=
3
8 ;
(2)
3
7 ×
1
5 ×
7
9 ,
=
3
7 ×
7
9 ×
1
5 ,
=
1
3 ×
1
5 ,
=
1
15 ;
(3)18×
2
3 ×
5
6 ,
=12×
5
6 ,
=10;
(4)
20
51 ×
17
30 ×9,
=
2
9 ×9,
=2;
(5)
11
36 ×27×
4
33 ,
=
11
36 ×
4
33 ×27,
=
1
27 ×27,
=1;
(6) 1
5
6 ×
2
3 ×
3
22 ,
=
11
6 ×
3
22 ×
2
3 ,
=
1
4 ×
2
3 ,
=
1
6 .