怎样算简便就怎样算.
12.7×99+12.7
25×32×0.125
(7.6×15+2.4×5)÷126
16.8-2.25-4.63.
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解:(1)12.7×99+12.7,
=12.7×(99+1),
=12.7×100,
=1270;
(2)25×32×0.125,
=(25×4)×(8×0.125),
=100×1,
=100;
(3)(7.6×15+2.4×5)÷126,
=(114+12)÷126,
=126÷126,
=1;
(4)16.8-2.25-4.63.
=16.8-(2.25+4.63),
=16.8-6.88,
=9.92.
解析分析:(1)12.7×99+12.7,应用乘法分配律进行简算;(2)25×32×0.125,转化为25×4×8×0.125,应用乘法结合律进行简算;(3)(7.6×15+2.4×5)÷126按照混合运算的运算顺序和计算法则脱式计算;(4)16.8-2.25-4.63.根据减法的运算性质,a-b-c=a-(b+c)进行简算.
点评:此题主要考查小数四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律、运算性质进行简便计算.