2.5×0.8×2.5×3.2=2.5×(0.8+3.2)
錯(cuò)誤
分析:在計(jì)算2.5×0.8×2.5×3.2時(shí),把0.8看作0.4×2,把3.2看作4×0.8,然后運(yùn)用運(yùn)算定律進(jìn)行簡(jiǎn)算.而2.5×0.8×2.5×3.2=2.5×(0.8+3.2)錯(cuò)用了運(yùn)算定律.
解答:2.5×0.8×2.5×3.2,
=2.5×0.4×2×2.5×4×0.8,
=(2.5×0.4)×(2.5×4)×0.8×2;
而原題錯(cuò)用了乘法分配律,因此,原題錯(cuò)誤.
故答案為:×.
點(diǎn)評(píng):解答此題,應(yīng)注意分析數(shù)據(jù),正確運(yùn)用運(yùn)算定律簡(jiǎn)算.
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