考点:小数四则混合运算,运算定律与简便运算
专题:运算顺序及法则,运算定律及简算
分析:(1)(7)(10)首先计算二级运算,然后再计算一级运算即可;
(2)(11)根据乘法结合律简算即可;
(3)(4)(5)(6)(9)根据乘法分配律简算即可;
(8)首先把0.48方程0.6×0.8,然后根据乘法结合律简算即可.
解答:
解:(1)2.08×3.4-7.06
=7.072-7.06
=0.012
(2)4.3×0.25×0.4
=4.3×(0.25×0.4)
=4.3×0.1
=0.43
(3)104×0.25
=100×0.25+4×0.25
=25+1
=26
(4)0.78×0.17-0.12×0.78
=0.78×(0.17-0.12)
=0.78×0.05
=0.039
(5)4.2×7.8+2.2×4.2
=4.2×(7.8+2.2)
=4.2×10
=42
(6)9.5×101
=9.5×100+9.5×1
=950+9.5
=959.5
(7)0.87×3.16+4.64
=2.7492+4.64
=7.3892
(8)0.48×1.25
=0.6×0.8×1.25
=0.6×(0.8×1.25)
=0.6×1
=0.6
(9)1.01×8.5
=1×8.5+0.01×8.5
=8.5+0.085
=8.585
(10)58.36×0.5+18.2
=29.18+18.2
=47.38
(11)0.25×5.8×0.4
=0.25×0.4×5.8
=0.1×5.8
=0.58
点评:此题主要考查了乘法运算定律在小数四则混合运算中的应用.