(I)原式=6.6-6.6+2+
2
3 +
1
2
=2+
4
6 +
3
6
=3
1
6 ;
(II)原式=
5
12 ×
8
15 ×
2
3
=
4
27 ;
(III)原式=-3-9×
4
9 +1
=-3-4+1
=-6;
(IV)原式=(
3
4 ×12-
7
6 ×12)÷(-1)÷(
10
15 -
9
15 )
=(9-14)÷(-1)×15
=5×15
=75.
(I)原式=6.6-6.6+2+
2
3 +
1
2
=2+
4
6 +
3
6
=3
1
6 ;
(II)原式=
5
12 ×
8
15 ×
2
3
=
4
27 ;
(III)原式=-3-9×
4
9 +1
=-3-4+1
=-6;
(IV)原式=(
3
4 ×12-
7
6 ×12)÷(-1)÷(
10
15 -
9
15 )
=(9-14)÷(-1)×15
=5×15
=75.