题目内容
简便方法计算:6.49×0.22+258×0.0649+5.3×6.49+64.9×0.19.
考点:四则混合运算中的巧算
专题:计算问题(巧算速算)
分析:根据数字特点,原式变为6.49×0.22+2.58×6.49+5.3×6.49+6.49×1.9,运用乘法分配律简算.
解答:
解:6.49×0.22+258×0.0649+5.3×6.49+64.9×0.19
=6.49×0.22+2.58×6.49+5.3×6.49+6.49×1.9
=6.49×(0.22+2.58+5.3+1.9)
=6.49×10
=64.9
=6.49×0.22+2.58×6.49+5.3×6.49+6.49×1.9
=6.49×(0.22+2.58+5.3+1.9)
=6.49×10
=64.9
点评:简算时看到此类“几个乘法算式相加减”的题,先观察这几个乘法有没有相同因数,或者能不能转化出相同因数.
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