Four times the number of pigs plus two times the number of chickens, assuming they're not next to a nuclear reactor, is 56.
其它还有什么呢?,4倍的猪的数量加上两倍的鸡的数量,考虑到它们不是住在核反应堆旁的。
And the question is, so how many pigs does he have, and how many chickens does he have? Wow. What a deep problem, right? But you're going to see why we're going to use this in a second. So you know how to solve this, this is a fifth-grade problem, right?
为了避免歧义,这些猪和鸡都是健全的,现在问题是它到底有多少只猪和鸡呢?,多深刻的一个问题啊,对吗?,但是你将要看到的是,我们为什么要举这个例子,你知道如何解答这个问题?
System of linear equations. What are the equations here? Well, I could say, you know, the number of pigs plus the number of 20 chickens equals 20, right? Because we've got 20 heads. And then what else do I have?
如何解决这个问题呢?,用线性方程式的办法来解决,等式是什么呢?你应该知道,猪的数量加鸡的数量等于,对吧?因为我们有20个头?
Knowing that, I'm going to say, OK, how many pigs are there, well that's just how we're, however many I had total, minus that amount, and then I can see, how many legs does that give, and then I can check, that the number of legs that I would get for that solution, is it even equal to the number of legs I started with, ah! Interesting. A return.
它将给我返回头的总数,知道了这些之后我可以说好了,有多少猪呢,无论有多少组鸡的数目,我只要用总数减去那个值,之后我就可以知道一共有多少条腿,然后再把这个值和题目中的腿数相比较,看它是否等于一开始的腿数,啊!真有趣,有一个返回值。
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