(1)
7
13 -0.4+
6
13 -
3
5 ,
=(
7
13 +
6
13 )-(0.4+0.6),
=1-1,
=0;
(2)
5
6 ×
14
15 ÷
7
8 ,
=
5
6 ×
14
15 ×
8
7 ,
=
8
9 ;
(3)(
3
8 +
7
16 )÷
13
16 ,
=
3
8 ×
16
13 +
7
16 ×
16
13 ,
=
6
13 +
7
13 ,
=1;
(4)20-[(
1
2 +
1
3 )÷
5
6 ]×1.2,
=20-[
5
6 ×
6
5 ]×1.2,
=20-1×1.2,
=20-1.2,
=18.8;
(5)
97
98 ×99,
=
97
98 × (98+1),
=
97
98 × 98 +
97
98 ×1,
=97 +
97
98 ,
=97
97
98 ;
(6)2007×(1-
1
2 )×(1-
1
3 )×(1-
1
4 )×…×(1-
1
2007 ),
=2007×
1
2 ×
2
3 ×
3
4 ×…×
2005
2006 ×
2006
2007 ,
=2007×
1
2007 ,
=1.