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欢迎观看年龄计算题

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我们开始吧

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题目我已列好了

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4年之后，阿里就是现在年龄的3倍

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请问阿里现在几岁？

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我们假设X

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这个X 写的有点大了

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我们假设 X = 阿里现在年龄

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或今年的年龄

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哈，我写字太潦草了，不好意思

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如果X是阿里现在的年龄

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题目说4年之后

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那4年之后阿里几岁呢？

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如果阿里现在是X岁

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那4年之后，阿里就是X+4 岁

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X+4岁 = 阿里4年后的年龄

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我们再读一下题目

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4年后,

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X+4 （框起来）就是4年后

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阿里就是现在年龄的3倍

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他现在是X岁

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4年之后

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X+4

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4年后

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我们把这个写成 X+4

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等于现在年龄的3倍

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我们知道他现在是X岁

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那就等于3X

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现在我们就只用算X等于多少了

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两边同时减去X

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2X=4

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X=2

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所以阿里现在是2岁

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我们再做一题吧

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刚才那题清楚了吧

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他今年2岁，4年之后

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他就是6岁

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也就是2岁的3倍

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这道题就解决了

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现在做下一道题

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我先清除一下屏幕

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我再录入一个题目

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Ok，题目： Nazrat 比 Umaima 大4岁

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2 年前

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Nazrat 比 Umaima 大5岁

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Nazrat 现在几岁？

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哈，这道题看起来还要难一些哟

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但我们肯定能解出答案来

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好了，想想

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我们要知道什么呢？

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我们要知道的是 Nazrat今年（现在）多少岁

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这是 Nazrat, 我们缩写成Naz吧

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这是 Umaima

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这儿是 今年（现在）

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做个表格式吧

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这儿是4年后，哦，说错了

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应该是2年前

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搞错了，看样子我还沉浸在上一道题呀

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所以，这儿是今年， 这儿是2年前

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我来画个表吧表示一下吧

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画的不好看，意思清楚就行

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我们现在要解出X等于多少

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就知道Nazrat 今年多少岁了？

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Naz今年X岁

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题目说Naz比Umaima大4岁

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让我把这部分线索划记一下

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我们从这句话得知

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Nazrat是X岁，Umaima就是x-4

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因为 Naz比 Umaima大4岁

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2年前

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如果naz今年是X岁，那2年前她多少岁呢

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那就是x-2

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这个很好理解，如果我现在是10岁

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2年前我就少2岁，就是8岁

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所以她今年是X岁的话

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2年前就是X-2

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UMAIMA 今年是X-4

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那2年前就比现在还少2岁

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那就是x-4-2 就等于x-6

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注意，她现在仍然比Naz小4岁

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我们看最后一句话

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2年前，Naz比Umaima大5岁

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现在我们的情况是，2年前

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Naz比Umaima大5岁

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Naz x-2 是 Umaima X-6 的5倍

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我们写下来

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Naz 2年前是 X-2

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我们从表中可以看出

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题目告诉我们

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2年前Naz年龄

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是Umaima年龄的5倍,

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Umaima2年前是X-6

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所以是 5(X-6）

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现在我们就只要解出X了

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X-2=5X-30

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两边同时减去X

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然后把等式左边和右边交换写下来

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嘿嘿，没把你弄糊涂吧

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4X-30=-2

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4X=28

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X =7

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所以我们解出这个方程式

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Naz今年7岁，你明白了吗？

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既然Naz今年7岁

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那Umaima今年就是3岁

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这个你明白吧

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就是相差4岁

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2年前 Nazi是5岁

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2年前 Umaima就是1岁，对吧

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7-6就是1岁

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对题目看一下就明白了

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Na比Umaima大4岁

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Naz是7岁

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Umaima就是3岁

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2年前Naz是5岁

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Umaima就是1岁

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问题解决了

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挺深奥的吧,嘿嘿

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你们现在已经可以试着解这类的题了吧

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以后我也会再演示一些题

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你要有不明白的地方

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随时都可以反复观看这个视屏

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加油！