Multiplication 2: Step By Step Like an N2 Mather

Oh, boy. Now it gets harder. Are you up for the challenge? Let's go!

Today we're gonna work on multiplication again, but this time, it's a little different. Remember when we did multiplication in the last lesson? Remember how in the last one we did 3x3? That was multiplying by just one digit. Now we're gonna multiply by TWO digits. This time, I'll write out the problem and give you a step-by-step guide on how to do it. Hopefully it will help you learn this type of multiplication. Ready? Here we go.

        45
x      32

First, we start out with the number 2, and multiply it by 4 & 5.

        45
x      32
          0
Oh, oh. 2x5 is 10!! But we can only fit only ONE digit in that section!! This is a time where we have to  carry.

        1
        45
x      32
          0
Now, back to where we were before. Don't forget, we need to add the carried number to the sum of this part.


        1
        45
x      32
        90
Now that we're done with this part, we need to go to that second digit. But before we do that, we need to erase (or delete, it depends on what you're using) that one that we had carried.



        45
x      32
        90
But now we need to add another row, and before we start adding with that one other digit, we need to put a zero there. This is because this digit is a ten.



        45
x      32
        90
          0
All right, now we can start multiplying.



        45
x      32
        90
        50
Wait, 3x5 is 15?! Don't forget about carrying!!

        1

        45
x      32
        90
        50

OK, back to the problem at hand. Don't forget about that carried number!!

        1

        45
x      32
        90
    1350
Now what do we do? Well, we're going to add the 2 numbers at the bottom. We won't have to erase that 1 at the top because it won't be in our way. You ready? Let's go!!


        1

        45
x      32
        90
+  1350
        40
Don't forget about carrying!! We'll also need to add that carried number to the sum of this column.


        1

        45
x      32
      1
        90
+  1350
      440
Last part!! Here we go!!



        1

        45
x      32
      1
        90
+  1350
    1440
So 1,440 is our total. We beat the challenge and pushed through multiplication!! AWESOME JOB!!!!
Next time we'll be facing an even greater challenge...
Join me as we get even deeper N2 Math!!

Happy New Year!!

I know, this isn't a lesson, but I just wanted to wish everybody a Happy New Year. It's been a great year, and I hope you've learned a lot so far. In 2013, I hope that I find better and more intuitive ways to teach you math. Again, Happy New Year to you.

By the way: I'm working on the 2nd multiplication lesson. It'll probably be up later today, if I have time.

Multiplication 1: Some Groups of This, Some Groups of That,

Wow. You're now halfway through the 4 kinds of arithmetic! Keep it up!

Today we'll learn a new kind of arithmetic. This one is called multiplication. You probably won't have trouble with the basics, but believe me, it gets a lot harder.

Multiplication is when you multiply in groups of itself. It's mainly just a writing shortcut for an addition problem at first. The problem we'll be working with today is 3x3. This means the answer will be the sum of 3 groups of 3. In the first group, we start out with 3. Then we add another group of 3. Can you guess what that would be? If you just said 6, you're right! If not, it's about time you went to www.khanacademy.org. It could really help you understand this concept better. Now, back to the problem. We now have 6, but we need to add yet another group of 3! Add 3 to 6, that would be 9! For those of you who got this right, keep up the good work! If not, please go to Khan Academy by clicking the link above. OK, now that we're done with this problem, what is our answer? Look back at the last number that I wrote. That, of course, would be 9!

Thank you for joining me while get deeper N2 Math!!

Subtraction 2: Testing... Testing...

Great job! Now you know the simple basics of subtraction, and you know how to borrow! Now, we'll practice even more subtraction! This time, instead of me getting you through the problem, I'll give YOU a problem to work on! All right, here we go...

   34

  -27

OK, now that you're done working on this problem, let's give you a grade on a scale of 1-10.

Key

32+ = 1

27-31 = 2

22-26 = 3

17-21 = 4

12-16 = 5

1-3 = 6

4-5 = 7

8-11 = 8

6 = 9

7 = 10

7 is the correct answer. If you got a grade from 1-5, I really recommend www.khanacademy.org.

Thanks for joining me today and I'll see you on the next N2 Math lesson/test!