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So I begin talking a little about mental math. Why mental math? So why is it that I am suggesting mental math on the ACT Math Test when, after all, you get a calculator? What's the point of mental math? Now I talked a little bit about mental math in the video on the calculator already.

And there'll be a few more videos talking about individual mental math techniques. And, of course, when you first hear about these techniques for reasoning with mental math. And you first are trying them they're gonna seem overwhelming and complex and so why would I be recommending these. Well what I'm gonna say will sound paradoxical, I recommend mental math because it's faster.

It's faster than using a calculator and, of course, this is a paradox. Because when you're first learning it it's not gonna seem faster it's gonna seem like a much longer way. And so what exactly is going on here? In order to explain this I'm gonna suggest an analogy. Suppose someone arrived in your town from another country, from someplace where bicycles don't exist.

Suppose this person had never seen a bicycle. Now where exactly this would be that they would have never seen a bicycle, let's forget that right now. Let's just suppose they show up, your age, and they've never seen a bicycle. We tell this person that this bicycle, it's an amazing thing. And you get on it, you can ride it, and it allows you to go much, much faster than when you're simply walking.

Hm, so the person's intrigued and so then that person they get on the bicycle, of course, they try a bicycle for a first time. And, of course, what's happening is they're falling off a lot, they bruise their elbows, they bruise their knees, they're just suffering by the end of the day. They haven't made much progress and by the end of the day they're in pain.

And they're just refusing to believe, this absolutely cannot be true, that using this device called a bicycle could make you go faster than walking. Now, of course, we've realized the nonsense in this because we've grown up in a world where there are bicycles. And, of course, maybe, you've seen the Tour de France. We know that bicycles can go really, really fast, but, of course, someone learning to use a bicycle for the first time their not gonna go fast.

it takes time and, of course, many of us learn bicycles when we're young. So that painful learning period is all when we're young and stupid before we build up the resistance to learning things like that. But the point is that when you're in the learning process, first learning how to do something it is gonna be slow. Why I'm saying all this because mental math is like that bike.

In the next few videos I'm gonna show you some techniques. The first time you do any of these techniques I guarantee it will not be faster than using a calculator. It may even be that the fifth or sixth time you do it it's still not faster than doing a calculator. You have to keep practicing them as you would have to keep practicing riding a bike.

Eventually, if you're faithful in practicing them, you will develop a technique that is faster than using a calculator, but it really takes a long view. You can't expect immediate gratification from these techniques that I'm gonna be teaching you. So with that in mind let's talk about mental math.

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