题目内容
能简要简. 2.8×4.5+15.3 | 0.125×8.7×0.8 | 18.3×0.54-8.3×0.54 |
19.89÷8.5÷0.65 | 28.5-18.5÷2.5 | 102×4.3 |
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)先算乘法再算加法;
(2)根据乘法的交换律简算;
(3)根据乘法的分配律简算;
(4)按照从左向右计算的运算法则计算即可;
(5)先算除法再算减法;
(6)根据乘法的分配律简算.
(2)根据乘法的交换律简算;
(3)根据乘法的分配律简算;
(4)按照从左向右计算的运算法则计算即可;
(5)先算除法再算减法;
(6)根据乘法的分配律简算.
解答:
解:(1)2.8×4.5+15.3
=12.6+15.3
=27.9
(2)0.125×8.7×0.8
=0.125×0.8×8.7
=0.1×8.7
=0.87
(3)18.3×0.54-8.3×0.54
=(18.3-8.3)×0.54
=10×0.54
=5.4
(4)19.89÷8.5÷0.65
=2.34÷0.65
=3.6
(5)28.5-18.5÷2.5
=28.5-7.4
=21.1
(6)102×4.3
=(100+2)×4.3
=100×4.3+2×4.3
=430+8.6
=438.6
=12.6+15.3
=27.9
(2)0.125×8.7×0.8
=0.125×0.8×8.7
=0.1×8.7
=0.87
(3)18.3×0.54-8.3×0.54
=(18.3-8.3)×0.54
=10×0.54
=5.4
(4)19.89÷8.5÷0.65
=2.34÷0.65
=3.6
(5)28.5-18.5÷2.5
=28.5-7.4
=21.1
(6)102×4.3
=(100+2)×4.3
=100×4.3+2×4.3
=430+8.6
=438.6
点评:完成本题要注意分析式中数据,运用合适的简便方法计算.
练习册系列答案
相关题目