题目内容
计算,能简算的要简算.
0.34×0.5×2 | 7.8×6.9+2.2×6.9 | 0.4÷(0.12-0.08)×1.27 | 102×0.45. |
解:
(1)0.34×0.5×2,
=0.34×(0.5×2),
=0.34×1,
=0.34;
(2)7.8×6.9+2.2×6.9,
=(7.8+2.2)×6.9,
=10×6.9,
=69;
(3)0.4÷(0.12-0.08)×1.27,
=0.4÷0.04×1.27,
=10×1.27,
=12.7;
(4)102×0.45,
=(100+2)×0.45,
=100×0.45+2×0.45,
=45+0.9,
=45.9.
分析:(1)根据乘法结合律进行简算;
(2)根据乘法分配律进行简算;
(3)先算小括号里面的减法,再算除法,最后算乘法;
(4)根据乘法分配律进行简算.
点评:四则运算,先弄清运算顺序,然后再进一步计算即可,能简算的要简算.
(1)0.34×0.5×2,
=0.34×(0.5×2),
=0.34×1,
=0.34;
(2)7.8×6.9+2.2×6.9,
=(7.8+2.2)×6.9,
=10×6.9,
=69;
(3)0.4÷(0.12-0.08)×1.27,
=0.4÷0.04×1.27,
=10×1.27,
=12.7;
(4)102×0.45,
=(100+2)×0.45,
=100×0.45+2×0.45,
=45+0.9,
=45.9.
分析:(1)根据乘法结合律进行简算;
(2)根据乘法分配律进行简算;
(3)先算小括号里面的减法,再算除法,最后算乘法;
(4)根据乘法分配律进行简算.
点评:四则运算,先弄清运算顺序,然后再进一步计算即可,能简算的要简算.
练习册系列答案
相关题目