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能简算的要简算.(34

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能简算的要简算.
3
4
能简算的要简算.(34
(1)(
3
4-
3

2
5)÷
1
5,
=[(1-
2
5)×
3
4]×5,
=
3

3
4×5,
=
9
4;
(2)(
2
3-
1
2+
1
6)÷
1
24,
=
1
3×24,
=8;
(3)7.28÷0.8÷12.5,
=7.28÷(0.8×12.5),
=7.28÷10,
=0.728;
(4)1.28×2.37-2.8×0.237,
=1.28×2.37-0.28×2.37,
=(1.28-0.28)×2.37,
=1×2.37,
=2.37;
(5)0.65×14+87×65%-
13
20,
=0.65×14+87×0.65-0.65,
=0.65×(14+87-1),
=0.65×100,
=65.