(1)25.3×12-33.46÷0.35,
=303.6-95.6,
=208;
(2)(
3
8 +
5
6 )÷
1
24 ,
=(
9
24 +
20
24 )÷
1
24 ,
=
29
24 ×24,
=29;
(3)2.5×13×0.4,
=(2.5×0.4)×13,
=1×13,
=13;
(4)
8
9 ÷[(
2
5 +
1
10 )×
3
4 ],
=
8
9 ÷[(
4
10 +
1
10 )×
3
4 ],
=
8
9 ÷[
1
2 ×
3
4 ],
=
8
9 ÷
3
8 ,
=
8
9 ×
8
3 ,
=
64
27 ;
(5)9.34-(2.34+0.49),
=(9.34-2.34)-0.49,
=7-0.49,
=6.51;
(6)
4
5 +
4
5 ×19,
=(1+19)×
4
5 ,
=20×
4
5 ,
=16.