(1)2.5×3.6
=2.5×4×0.9
=10×0.9
=9;
(2)(0.25+0.125)×8
=0.25×8+0.125×8
=2+1
=3;
(3)29
4
5 -
7
8 +
1
5 -
1
8
=(29
4
5 +
1
5 )-(
7
8 +
1
8 )
=30-1
=29.
(1)2.5×3.6
=2.5×4×0.9
=10×0.9
=9;
(2)(0.25+0.125)×8
=0.25×8+0.125×8
=2+1
=3;
(3)29
4
5 -
7
8 +
1
5 -
1
8
=(29
4
5 +
1
5 )-(
7
8 +
1
8 )
=30-1
=29.