WEBVTT

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上集视频中我们做了99.061除以100

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是手算的

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用的长除法

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这集视频我要告诉大家

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除以10时的一个运算技巧

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99.061如果是乘以10的乘方

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原数会变大

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每次乘以10

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小数点要右移一位

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那么99.061乘以10

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就等于990.61

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注意 小数点正好是向右移了一位

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如果--我随便换个颜色--

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99.061除以10

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小数点就要向相反方向移动

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就会是9.9061

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除以100 就是除以10除了两次

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向左移两位

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如果是99.061除以100

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我这么写

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我已经写出来了

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如果是除以100

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向左移一位是除以10

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再移一位

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又除以10

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那99.061除以100等于0.99061

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小数点左移两位

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小数点前边要添0

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读起来更方便