56×(-) 9.75-3.42-5.58 125×0.25×3.2(-)× ×+÷8 +×.
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解:(1)56×(-),
=56×-56×,
=24-21,
=3;
(2)9.75-3.42-5.58,
=9.75-(3.42+5.58),
=9.75-9,
=0.75;
(3)125×0.25×3.2,
=125×0.25×4×0.8,
=125×0.8×0.25×4,
=100×1,
=100;
(4)(-)×,
=××,
=
=,
=;
(5)×+÷8
=×+×,
=×(),
=×,
=;
(6)+×,
=×(3+),
=×,
=.
解析分析:(1)根据乘法的分配律作答;
(2)根据连续减去两个数,等于减去这两个数的和;
(3)将3.2拆成0.8和4的积,再根据乘法的交换律作答;
(4)、(5)、(6)根据乘法的分配律作答.
点评:解答此题的关键是,运用乘法的分配律及乘法的交换律,使计算简便.