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All right. Let's take a look at some basic arithmetic.

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Now, when I say basic arithmetic, all I mean here is math,

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and I don't mean advanced math.

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It's not algebra, it's not calculus,

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it's nothing complicated.

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But we do need to know how we can add subtract, divide, multiply,

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and we'll probably even use exponents, oops, and give you a

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sneak peek there, exponents.

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So in Python, and in most programming languages,

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these rules hold true.

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So when you're trying to add a number you can add, let's

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say 89 + 11.

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And that's just simply going to add the number. That will give us 100.

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And likewise, if we wanted to subtract a number, it's the

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subtract symbol, so 100 - 49 is equal to 51.

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Dividing is as simple as 100,

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and then you use a '/', divided by, let's divide that by

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10. That will give us 10.

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And if we want to multiply, we could do 9 times 9,

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and to multiply it's just an '*'.

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So it's the little '*' symbol.

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And that's how we multiply.

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And exponents are one we're going to be using throughout

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to this course quite frequently.

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And in exponents in some programming languages is like three

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to the power of three, 3^3,

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but in Python we use two asterisks side by side, '**'

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So three to the power of three, 3**3 is going to give us 27, 3

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times 3 times 3; 3 times 3 times 3 is what that is.

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And that is how we do an exponent.

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Now, there's one other thing that we're going to look at

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a little bit down the road, and it's called modulus, modulus.

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And you know, when you divide a number, and you get a remainder,

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that's what a modulus is.

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So if you divide 10 by 3, you're going to get 3 with

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some remainder.

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So 3.333.

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Now what if you wanted to get that remainder as a number?

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So 3 goes into 10, 3 times 3-6-9, and there's a remainder of 1.

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We can do that with the percent(%) symbol.

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So we take one number and we divide it by, not divided by,

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we modulus it by a second number, and we hit enter, and we get 1.

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So what that means is 3 goes into 10, 3 times 3-6-9,

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and then 10 minus 9 is going to be 1, and that's your

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remainder. Beyond that, we're actually not going to be doing

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too much arithmetic in this course.

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And believe it or not, there's actually not a lot of mathematics

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in most programming these days.

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There is mathematics

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if you get into data science, or if you want to get into, even

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some forms of machine learning has some math,

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but for the most part programming does not have a lot of

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math, and so by no means do you need to be a mathematician

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in order to learn how to program.

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People always think that, "Oh, because you're a programmer,

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you must be good at math".

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But that simply does not have to be true.

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So that is basic arithmetic.

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We add with a '+' symbol, we subtract with the '-' or the minus symbol,

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we divide with a '/',

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we multiply with an asterisk or the star, '*',

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we exponent with two stars, '**',

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and this is just multiplying three numbers together, and

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we modulus or get the remainder with a percent (%) symbol.