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

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Time Narration
00:00 Welcome to this tutorial on basic arithmetic operators.
00:03 I'll first go through plus, minus, multiply and divide operations.
00:09 These are written as p lus, minus, multiply as an asterisk and divide as a forward slash.
00:17 So, I will have 2 variables.
00:20 I'll create a variable called "num1" and I'll save that as value equal to "10" and "num2" is equal to "2".
00:30 So, these are both integer numbers with no decimal point.
00:34 Okay, now, say I want to add "num1" and "num2" together.
00:40 So I echo out the answer of "num1" added to "num2".
00:44 Let's test it out.
00:47 So, that's "12". 10 and 2, num1 and num2, when 10 and 2 are added, the answer is "12".
00:55 Okay now let's try minus. We will just replace the minus symbol there.
01:01 Refresh and that will be "8".
01:05 Now lets try multiplication. 10 times 2 is 20 and we've got "20".
01:11 Next, 10 divided by 2 is just half of 10 which is "5".
01:18 Now, what we can do is we can add something on the end of this.
01:24 So, let's say this is divided by num2.
01:27 So, what I think this operation will do is, it will add "num1" and "num2", so that is 10 and 2 which will give us 12 and then 12 divided by 2.
01:39 So, 12 divided by 2 should give 6.
01:43 But actually what this does is it takes num2 and divides it by num2 which will give 1 and add num1 to that.
01:56 So, that means, instead of 6 we will get 11.
02:00 Now, the reason for this is that division operator will always work before addition operator. The same with multiply
02:10 Now, to solve this, we should put brackets.
02:16 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.
02:29 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.
02:39 Let's refresh that and we can see that it worked!
02:43 So, these are the basic arithmetic operators which are simple to use.
02:48 If you come across any problems, always verify your calculations with a calculator to make sure they're working.
02:55 We'll see a few more of these soon.
02:58 We'll learn about the increment arithmetic operator which increments by 1 but I'll use that a little later.
03:05 So, practice these and make sure you learn them well.
03:09 Thanks for watching. This is Arvind dubbing for the Spoken Tutorial project.

Contributors and Content Editors

Minal, Pratik kamble, Sandhya.np14