PHP-and-MySQL/C2/Arithmatic-Operators/English

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Time Narration
0:00 Welcome to this tutorial on basic arithmetic operators.
0:03 I'll first go through plus, minus, multiply and divide operations.
0:09 These are written as p lus, minus, multiply as an asterisk and divide as forward slash.
0:16 So, I will have 2 variables.
0:19 I'll create a variable called "num1" and I'll save that as value equal to "10" and "num2" is equal to "2".
0:28 So, these are both integer numbers with no decimal point.
0:33 Okay, now, say I want to add "num1" and "num2" together.
0:38 So I echo out the answer of "num1" added to "num2".
0:44 Let's test it out.
0:50 So, that's "12". 10 and 2, num1 and num2, when 10 and 2 are added, the answer is "12".
0:54 Okay now let's try minus. We will just replace the minus symbol there.
1:01 Refresh and that will be "8".
1:04 Now lets try multiplication. 10 times 2 is 20 and we've got "20".
1:10 Next, 10 divided by 2 is just half of 10 which is "5".
1:16 Now, what we can do is we can add something on the end of this.
1:23 So, let's say this is divided by num2.
1:27 Now, what I think this operation will do is, it will add "num1" and "num2", so that is add 10 and 2 which will give us 12 and then 12 divided by 2.
1:39 So, 12 divided by 2 should give 6.
1:42 But what this actually does is it takes num2 and divides it by num2 which will give 1 and add num1 to that.
1:55 So, that means, instead of 6 we will get 11.
2:00 Now, the reason for this is that division operator will always work before addition operator. The same with multiply
2:09 Now, to solve this, we should put brackets.
2:14 The brackets will say - we'll take this operation first, do whatever is in here and then continue to divide by whatever this could be an integer or a variable.
2:27 So, here what it will do is num1 plus num2 which is 10 plus 2 which gives us 12 divided by 2 which should give us 6.
2:38 Let's refresh that and we can see that it worked!
2:43 So, these are the basic arithmetic operators which are simple to use.
2:47 If you come across any problems, always verify your calculations with a calculator to make sure they're working.
2:55 We'll see a few more of these soon.
2:57 We'll learn about the increment arithmetic operator which increments by 1 but I'll use that a little later.
3:05 So, practice these and make sure you learn them well.
3:09 Thanks for watching. This is Arvind dubbing for the Spoken Tutorial project.

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Chandrika