WEBVTT

00:00:00.880 --> 00:00:05.805
At this point I think you know a little bit about what multiplication is.

00:00:05.805 --> 00:00:09.025
Or "multi"-plication.

00:00:09.025 --> 00:00:13.315
What we're going to do in this video is to give you just a ton of more practice,

00:00:13.315 --> 00:00:17.706
and start you on your memorization of the multiplication tables.

00:00:17.706 --> 00:00:20.009
And if you watch enough Khan Academy videos,

00:00:20.009 --> 00:00:21.279
and hopefully you will in the future,

00:00:21.279 --> 00:00:24.540
you'll realize that I'm normally not a big fan of memorization.

00:00:24.550 --> 00:00:26.385
But the one thing about multiplication

00:00:26.385 --> 00:00:31.220
is if you memorize your multiplication tables that we'll start to do in this video,

00:00:31.220 --> 00:00:33.850
it'll pay huge benefits the rest of your life.

00:00:33.850 --> 00:00:36.724
So I promise you, do it now, you'll never forget it,

00:00:36.724 --> 00:00:39.547
and the rest of your life everything will be--

00:00:39.547 --> 00:00:41.517
well, I don't want to make false promises to you,

00:00:41.517 --> 00:00:45.790
but they'll be better than if you didn't memorize your multiplication tables.

00:00:45.790 --> 00:00:47.290
So what are the multiplication tables?

00:00:47.290 --> 00:00:49.745
Well that's all of the different numbers

00:00:49.745 --> 00:00:50.850
times each other.

00:00:50.850 --> 00:00:53.590
So let's actually do a little bit of review.

00:00:53.600 --> 00:00:58.900
So if I say, what is two times one?

00:00:58.900 --> 00:01:02.270
That is equal to two plus itself one time.

00:01:02.280 --> 00:01:05.010
So this is equal to just two.

00:01:05.010 --> 00:01:07.060
That's two plus itself one time.

00:01:07.060 --> 00:01:08.059
I don't have to say plus anything

00:01:08.059 --> 00:01:09.430
because there's only one two there.

00:01:09.430 --> 00:01:13.460
I could also write this as one plus itself two times.

00:01:13.460 --> 00:01:15.390
So that's also one plus one.

00:01:15.400 --> 00:01:17.580
Well that also equals two.

00:01:17.590 --> 00:01:18.210
Fair enough.

00:01:18.210 --> 00:01:19.901
So two times one is two.

00:01:19.901 --> 00:01:22.722
And if you watched the last video, what's two times zero?

00:01:22.722 --> 00:01:23.516
Well that's zero.

00:01:23.516 --> 00:01:26.660
So you don't have to memorize your zero multiplication tables

00:01:26.670 --> 00:01:30.560
because everything times zero is zero, or zero times anything is zero.

00:01:30.560 --> 00:01:31.090
So let's see.

00:01:31.090 --> 00:01:33.682
What's two times two?

00:01:33.682 --> 00:01:35.988
Two times two.

00:01:35.988 --> 00:01:37.254
Well, this is equal to--

00:01:37.254 --> 00:01:39.460
we're going to add two to itself two times.

00:01:39.460 --> 00:01:41.830
So that's two plus two.

00:01:41.840 --> 00:01:42.770
And there's only a way to do that.

00:01:42.780 --> 00:01:45.480
I could say take this two and add it to itself two times,

00:01:45.480 --> 00:01:46.680
but it's the same thing.

00:01:46.680 --> 00:01:47.610
And what's two plus two?

00:01:47.620 --> 00:01:49.450
That's equal to four.

00:01:49.450 --> 00:01:51.400
What's two times three?

00:01:51.400 --> 00:01:57.900
Two times three is equal to two plus two plus two.

00:01:57.900 --> 00:02:03.355
It can also be equal to three plus three.

00:02:03.355 --> 00:02:04.905
We learned in a previous video

00:02:04.920 --> 00:02:07.498
this statement can be written either of these ways.

00:02:07.498 --> 00:02:09.380
And in either case, what's it equal to?

00:02:09.397 --> 00:02:10.282
Well three plus three

00:02:10.282 --> 00:02:12.028
is the same thing as two plus two plus two,

00:02:12.028 --> 00:02:14.774
and that's equal to six.

00:02:14.774 --> 00:02:15.812
All right.

00:02:15.812 --> 00:02:18.138
Now what is two times four?

00:02:18.153 --> 00:02:20.686
Two times four.

00:02:20.686 --> 00:02:26.065
Well that's equal to two plus two plus two plus two.

00:02:26.065 --> 00:02:29.870
And notice, it's exactly what two times three was.

00:02:29.870 --> 00:02:32.610
Two times three was that.

00:02:32.620 --> 00:02:36.490
I have that here, but now I'm just adding another two to it.

00:02:36.490 --> 00:02:39.740
So if we're too lazy to sit here and add two plus two is four.

00:02:39.740 --> 00:02:40.710
Four plus two is six.

00:02:40.710 --> 00:02:41.802
Instead of doing that, we could say,

00:02:41.802 --> 00:02:45.680
hey look, we already know that this thing over here, this was six.

00:02:45.680 --> 00:02:48.300
We figured it out in the previous line right there.

00:02:48.310 --> 00:02:51.550
We figured out this is six, so we could just say, oh, two times four

00:02:51.560 --> 00:02:55.610
is going to be two more than that, which is equal to eight.

00:02:55.610 --> 00:02:57.480
And you should hopefully see that pattern.

00:02:57.490 --> 00:03:01.907
As we go from two times one, to two times two,

00:03:01.907 --> 00:03:03.760
to two times three, what's happening?

00:03:03.770 --> 00:03:05.500
How much are we going up by?

00:03:05.500 --> 00:03:08.120
From two to four we're going plus two.

00:03:08.120 --> 00:03:11.300
From four to six we're going plus two.

00:03:11.310 --> 00:03:13.340
And then from six to eight we're going plus two.

00:03:13.340 --> 00:03:15.685
So you could figure out what two times five is,

00:03:15.685 --> 00:03:16.950
even without doing the addition.

00:03:16.960 --> 00:03:23.430
Two times five is equal to two plus two plus two plus two plus two.

00:03:23.430 --> 00:03:26.070
It could also be written as five plus five.

00:03:26.080 --> 00:03:29.110
Two times four could've been written as four plus four as well.

00:03:29.120 --> 00:03:30.490
And what's that equal to?

00:03:30.500 --> 00:03:33.090
We could add all of these up or we could add these two up.

00:03:33.090 --> 00:03:36.285
Or we could just say it's going to be two more than two times four.

00:03:36.285 --> 00:03:38.564
So it's going to be ten.

00:03:38.564 --> 00:03:41.780
I'll finish the two times tables.

00:03:41.780 --> 00:03:45.280
And I think you see all of the patterns that emerge from it.

00:03:45.280 --> 00:03:47.710
So two times six.

00:03:47.710 --> 00:03:51.580
That's going to be two plus itself six times.

00:03:51.595 --> 00:03:55.369
Let's see. One, two, three, four, five, six,

00:03:55.369 --> 00:03:58.690
which should also be equal to six plus itself two times.

00:03:58.690 --> 00:04:00.620
This could be interpreted either way.

00:04:00.620 --> 00:04:02.980
And that's going to be equal to twelve.

00:04:02.990 --> 00:04:06.898
Once again, two more than two times five

00:04:06.898 --> 00:04:09.710
because we're adding two to itself one more time.

00:04:09.710 --> 00:04:12.290
So it's going to be two more.

00:04:12.300 --> 00:04:13.880
Let's keep going.

00:04:13.880 --> 00:04:16.540
So two times seven.

00:04:16.550 --> 00:04:20.148
Two times seven is equal to--

00:04:20.163 --> 00:04:24.104
well, I could write two plus two plus two plus two--

00:04:24.104 --> 00:04:27.230
this is getting tiring-- plus two plus two.

00:04:27.240 --> 00:04:27.800
Is that seven?

00:04:27.810 --> 00:04:31.200
One, two, three, four, five, six, seven.

00:04:31.200 --> 00:04:33.849
And that's the same thing as seven plus seven,

00:04:33.849 --> 00:04:37.370
which you may or may not know is equal to fourteen.

00:04:37.370 --> 00:04:39.550
You could just say hey, that's going to be two more than twelve.

00:04:39.560 --> 00:04:43.630
So twelve plus one plus two is-- twelve plus one is thirteen.

00:04:43.630 --> 00:04:45.530
Twelve plus two is fourteen.

00:04:45.540 --> 00:04:47.580
All right, let's just keep going.

00:04:47.580 --> 00:04:50.740
Two times eight.

00:04:50.750 --> 00:04:53.810
I could do all of this business here where I add the twos

00:04:53.810 --> 00:04:56.660
or I could say, look, it's just going to be two more than two times seven.

00:04:56.670 --> 00:04:59.528
So I could say it's going to be fourteen plus two.

00:04:59.528 --> 00:05:00.470
I'm just adding two to that one.

00:05:00.480 --> 00:05:01.822
So I could say it's sixteen.

00:05:01.822 --> 00:05:05.610
Or I could also say that's eight plus eight.

00:05:05.620 --> 00:05:06.800
That's also sixteen.

00:05:06.810 --> 00:05:08.174
I could have done all the twos out,

00:05:08.174 --> 00:05:15.040
but if you like you could do that for your own benefit and learning.

00:05:15.040 --> 00:05:17.848
We're almost-- well, we could go forever

00:05:17.848 --> 00:05:19.360
because there is no largest number.

00:05:19.370 --> 00:05:21.510
I can keep going.

00:05:21.510 --> 00:05:24.970
Two times nine times ten times one hundred times one thousand times one million.

00:05:24.980 --> 00:05:26.642
But I'm going to stop at twelve

00:05:26.642 --> 00:05:28.760
because that tends to be what people need to memorize.

00:05:28.770 --> 00:05:32.330
But if you really want to be a "mathelete"

00:05:32.330 --> 00:05:34.260
you want to go up to twenty.

00:05:34.260 --> 00:05:36.790
But let's go to two times nine.

00:05:36.790 --> 00:05:38.810
That's going to be two more than two times eight.

00:05:38.810 --> 00:05:40.990
It's going to be eighteen.

00:05:40.990 --> 00:05:42.690
Or that's nine plus nine.

00:05:42.690 --> 00:05:44.060
Also eighteen.

00:05:44.060 --> 00:05:45.930
What's two times ten?

00:05:45.940 --> 00:05:47.940
And ten times tables are interesting.

00:05:47.940 --> 00:05:49.550
And we're going to see a pattern there in a second

00:05:49.560 --> 00:05:53.040
when we try to complete an entire times tables.

00:05:53.040 --> 00:05:54.640
So two times ten?

00:05:54.640 --> 00:05:56.800
Two more than two times nine.

00:05:56.810 --> 00:05:59.050
It's twenty.

00:05:59.050 --> 00:06:01.050
Or we could also say that's ten plus ten.

00:06:01.060 --> 00:06:03.360
Ten plus itself two times.

00:06:03.360 --> 00:06:05.060
Now what's interesting about this?

00:06:05.060 --> 00:06:09.115
This looks just like a two with a zero added.

00:06:09.115 --> 00:06:10.690
And you're going to see that with anything times ten,

00:06:10.690 --> 00:06:12.295
you just put a zero on the right.

00:06:12.295 --> 00:06:14.130
And you can think about why that is.

00:06:14.130 --> 00:06:16.410
You can view this as two tens is twenty.

00:06:16.420 --> 00:06:18.000
That's what twenty is.

00:06:18.000 --> 00:06:19.540
We're almost done.

00:06:19.550 --> 00:06:21.820
Let's do two times eleven.

00:06:21.820 --> 00:06:25.920
Two times eleven is going to be two more than this right here.

00:06:25.930 --> 00:06:27.830
It's going to be twenty-two.

00:06:27.830 --> 00:06:29.530
Another interesting pattern.

00:06:29.540 --> 00:06:32.220
I have the number repeated twice-- a two and a two.

00:06:32.220 --> 00:06:33.160
Interesting.

00:06:33.170 --> 00:06:35.818
Something to watch out for

00:06:35.818 --> 00:06:38.690
as we look at other multiplication tables.

00:06:38.704 --> 00:06:40.140
And then finally--

00:06:40.140 --> 00:06:42.129
and it's not finally, we could keep going--

00:06:42.129 --> 00:06:44.682
Two times-- that's too dark of a color.

00:06:44.682 --> 00:06:47.059
Two times twelve.

00:06:47.059 --> 00:06:50.540
Two times twelve is going to be two more than two times eleven.

00:06:50.550 --> 00:06:51.826
That's twenty-four.

00:06:51.826 --> 00:06:54.160
We could have also written that as twelve plus twelve.

00:06:54.170 --> 00:06:56.110
Or we could've said two plus two plus two plus two

00:06:56.110 --> 00:06:57.840
plus two... twelve times.

00:06:57.850 --> 00:06:59.660
It all gets you to twenty-four.

00:06:59.670 --> 00:07:00.961
So that's the two times tables

00:07:00.961 --> 00:07:01.970
and I think you see the pattern.

00:07:01.980 --> 00:07:04.755
Every time you multiply it by one higher number

00:07:04.755 --> 00:07:06.670
you just add two to that number.

00:07:06.680 --> 00:07:08.748
So now that we see that pattern,

00:07:08.748 --> 00:07:11.950
let's see if we can complete a multiplication table.

00:07:11.950 --> 00:07:16.260
So what I want to do, I'm going to write all the numbers.

00:07:16.270 --> 00:07:18.485
Let's see.

00:07:18.485 --> 00:07:19.361
I hope I have space for this.

00:07:19.361 --> 00:07:29.430
One, two, three, four, five, six, seven, eight, nine.

00:07:29.430 --> 00:07:30.910
Actually, I'll just do it till nine.

00:07:30.920 --> 00:07:31.830
I'll just keep going.

00:07:31.830 --> 00:07:32.970
Nine.

00:07:32.970 --> 00:07:34.106
Actually I won't have space to do that

00:07:34.106 --> 00:07:35.680
because I want you to see the entire table.

00:07:35.680 --> 00:07:37.045
So I'm just going up till nine here,

00:07:37.045 --> 00:07:39.590
but I encourage you after this video to complete it on your own.

00:07:39.600 --> 00:07:42.880
Maybe if we have time I'll complete it here as well.

00:07:42.880 --> 00:07:45.887
So these are the first numbers that I'm going to multiply.

00:07:45.887 --> 00:07:52.060
And I'm going to multiply it times one, two, three, four,

00:07:52.060 --> 00:07:57.650
five, six, seven, eight, and nine.

00:07:57.650 --> 00:08:00.183
What I'm going to do is, I'm going to--

00:08:00.183 --> 00:08:01.298
So first of all--

00:08:01.298 --> 00:08:03.321
Actually I should have written this one under--

00:08:03.321 --> 00:08:04.710
well, what's one times one?

00:08:04.720 --> 00:08:06.110
So this is the way I'm going to view it.

00:08:06.120 --> 00:08:08.730
Whatever is one times one I'm going to write here.

00:08:08.730 --> 00:08:09.970
Well that's one.

00:08:09.970 --> 00:08:11.510
What's one times two?

00:08:11.510 --> 00:08:12.400
That's two.

00:08:12.410 --> 00:08:13.730
What's one times three?

00:08:13.740 --> 00:08:14.360
That's three.

00:08:14.360 --> 00:08:15.866
One times anything is that number,

00:08:15.866 --> 00:08:21.360
so I can just write four, five, six, seven, eight, nine.

00:08:21.370 --> 00:08:23.540
One times nine is nine.

00:08:23.540 --> 00:08:24.540
Fair enough.

00:08:24.540 --> 00:08:26.300
Now let's do the two times tables.

00:08:26.310 --> 00:08:27.570
I'll do that in a blue.

00:08:27.570 --> 00:08:30.270
Actually, let me do one in that color

00:08:30.285 --> 00:08:33.980
and now in maybe a darker blue I'll do the two times tables.

00:08:33.990 --> 00:08:35.250
What's two times one?

00:08:35.250 --> 00:08:36.430
That's two.

00:08:36.440 --> 00:08:37.690
It's the same thing as one times two.

00:08:37.700 --> 00:08:40.000
Notice, these two numbers are the same thing.

00:08:40.000 --> 00:08:41.700
What's two times two?

00:08:41.710 --> 00:08:43.000
That's four.

00:08:43.000 --> 00:08:44.610
Two times three is six.

00:08:44.620 --> 00:08:45.840
We just did this.

00:08:45.840 --> 00:08:49.821
Every time you increment or you multiply by a higher number,

00:08:49.821 --> 00:08:51.190
you just add by two.

00:08:51.190 --> 00:08:52.840
Two times four is eight.

00:08:52.850 --> 00:08:55.110
Same thing as four times two.

00:08:55.120 --> 00:08:57.260
Two times five is ten.

00:08:57.260 --> 00:08:59.010
Two times six is twelve.

00:08:59.010 --> 00:09:00.660
I'm just adding two every time.

00:09:00.670 --> 00:09:03.970
Up here I added one from every step, here I'm adding two.

00:09:03.980 --> 00:09:06.830
Two times seven, fourteen.

00:09:06.830 --> 00:09:09.813
Two times eight, sixteen.

00:09:09.813 --> 00:09:12.970
Two times nine, eighteen.

00:09:12.980 --> 00:09:17.789
All right, let's do our three times tables.

00:09:17.789 --> 00:09:20.508
I'll do it in yellow.

00:09:20.508 --> 00:09:21.783
Yellow.

00:09:21.783 --> 00:09:23.828
Three times one is three.

00:09:23.828 --> 00:09:25.350
Notice, three times one is three.

00:09:25.360 --> 00:09:26.910
One times three is three.

00:09:26.910 --> 00:09:28.740
These are the same values.

00:09:28.750 --> 00:09:32.158
Three times two is the same thing as two times three.

00:09:32.158 --> 00:09:37.640
Three times two should be the same thing as two times three.

00:09:37.640 --> 00:09:39.680
So it's six.

00:09:39.690 --> 00:09:40.485
And that makes sense.

00:09:40.485 --> 00:09:45.690
Three plus three is six or two plus two plus two is six.

00:09:45.690 --> 00:09:47.780
So every time here we're going to increase by three.

00:09:47.780 --> 00:09:48.880
You see the pattern.

00:09:48.880 --> 00:09:51.000
Three times three is nine.

00:09:51.010 --> 00:09:52.852
Three plus three plus three.

00:09:52.852 --> 00:09:54.725
So we went from three to six to nine.

00:09:54.736 --> 00:09:57.001
So three times four is going to be twelve.

00:09:57.001 --> 00:09:58.850
I'm just adding three every time.

00:09:58.850 --> 00:10:00.642
Twelve plus three is fifteen.

00:10:00.642 --> 00:10:03.404
Fifteen plus three is eighteen.

00:10:03.404 --> 00:10:05.580
Eighteen plus three is twenty-one.

00:10:05.580 --> 00:10:08.080
Twenty-one plus three is twenty-four.

00:10:08.090 --> 00:10:10.500
Twenty-four plus three is twenty-seven.

00:10:10.500 --> 00:10:13.110
So three times nine is twenty-seven.

00:10:13.120 --> 00:10:14.840
Three times eight is twenty-four.

00:10:14.840 --> 00:10:19.094
So if you were to say eight plus eight plus eight, it would be twenty-four.

00:10:19.094 --> 00:10:20.180
Let's see if I can--

00:10:20.180 --> 00:10:21.544
So now I'm going to speed it up a little bit,

00:10:21.544 --> 00:10:22.830
now that we see the pattern.

00:10:22.840 --> 00:10:24.088
And you should do this on your own

00:10:24.088 --> 00:10:26.970
and you really should memorize everything we're doing.

00:10:26.980 --> 00:10:30.495
You should actually go all the way up to twelve in both directions.

00:10:30.495 --> 00:10:31.057
So let's see.

00:10:31.057 --> 00:10:35.330
Four times one is four.

00:10:35.330 --> 00:10:37.640
I'm just going to go up by increments of four.

00:10:37.640 --> 00:10:40.080
So four plus four is eight.

00:10:40.090 --> 00:10:41.960
Eight plus four is twelve.

00:10:41.970 --> 00:10:43.920
Twelve plus four is sixteen.

00:10:43.920 --> 00:10:46.450
Sixteen plus four is twenty.

00:10:46.460 --> 00:10:48.460
Twenty plus four is twenty-four.

00:10:48.460 --> 00:10:51.460
Four times six is twenty-four.

00:10:51.470 --> 00:10:52.970
Four times seven, twenty-eight.

00:10:52.980 --> 00:10:54.250
I'm just going up by four.

00:10:54.250 --> 00:10:58.740
Thirty-two and thirty-six.

00:10:58.750 --> 00:11:01.490
All right, five times one.

00:11:01.490 --> 00:11:06.670
Five times one is going to be five.

00:11:06.670 --> 00:11:09.565
Actually, we know that anything that-- well, I want us to keep changing colors,

00:11:09.565 --> 00:11:11.400
so I'll just do it in rows like this.

00:11:11.410 --> 00:11:12.570
Five times one is five.

00:11:12.580 --> 00:11:15.780
Five times two is ten.

00:11:15.780 --> 00:11:17.260
Five times three is fifteen.

00:11:17.260 --> 00:11:18.430
I'm just going to increase by five.

00:11:18.440 --> 00:11:20.687
Five times tables are very fun as well

00:11:20.687 --> 00:11:24.120
because every number you're going to add-- if we multiply five times--

00:11:24.120 --> 00:11:25.870
well, we'll learn about even and odd in the future.

00:11:25.880 --> 00:11:30.241
But every other number in its times tables is going to end with a five,

00:11:30.241 --> 00:11:32.240
and then every other one's going to end with a zero.

00:11:32.250 --> 00:11:34.790
Because if you add five to fifteen you get twenty.

00:11:34.790 --> 00:11:41.871
You get twenty-five, thirty, thirty-five, forty, forty-five.

00:11:41.871 --> 00:11:43.380
Fair enough.

00:11:43.380 --> 00:11:47.120
Six times tables, let me do it in green.

00:11:47.120 --> 00:11:48.210
Six times one is six.

00:11:48.220 --> 00:11:49.080
That's easy.

00:11:49.080 --> 00:11:50.800
You add six to that, you get twelve.

00:11:50.800 --> 00:11:52.490
You add six to that, you get eighteen.

00:11:52.500 --> 00:11:54.250
You add six to that, you get twenty-four.

00:11:54.250 --> 00:11:56.220
You add six to that, you get thirty.

00:11:56.220 --> 00:12:01.220
Then you go six more, thirty-six, forty-two, forty-eight.

00:12:01.220 --> 00:12:04.620
Forty-eight plus six is fifty-four.

00:12:04.620 --> 00:12:07.620
So six times nine is fifty-four.

00:12:07.620 --> 00:12:08.990
All right, we're almost there.

00:12:09.000 --> 00:12:11.610
Seven times one, that's seven.

00:12:11.620 --> 00:12:13.520
Seven times one is seven.

00:12:13.520 --> 00:12:15.610
Seven times two is fourteen.

00:12:15.620 --> 00:12:17.740
Seven times three, twenty-one.

00:12:17.740 --> 00:12:20.040
Seven times four, twenty-eight.

00:12:20.040 --> 00:12:23.512
Seven times five, what's twenty-eight plus seven?

00:12:23.512 --> 00:12:25.130
Let's see, if you add two you get to thirty.

00:12:25.130 --> 00:12:27.700
Then you add five, it's thirty-five.

00:12:27.710 --> 00:12:29.480
Seven times six, forty-two.

00:12:29.490 --> 00:12:32.640
Seven times seven, forty-nine.

00:12:32.640 --> 00:12:34.775
Seven times eight--

00:12:34.775 --> 00:12:37.830
seven times is going to be seven plus this, so it's fifty-six.

00:12:37.830 --> 00:12:41.580
I always used to get confused between seven times eight being fifty-six

00:12:41.590 --> 00:12:43.610
and six times nine being fifty-four.

00:12:43.620 --> 00:12:46.705
So now that I pointed out to you that I always got confused between those two,

00:12:46.705 --> 00:12:49.389
it's your job not to be confused by those two.

00:12:49.390 --> 00:12:52.610
Seven times eight you could say has the six in it.

00:12:52.620 --> 00:12:54.850
Six times nine doesn't have the six in it.

00:12:54.850 --> 00:12:56.080
That's the way I think of it.

00:12:56.080 --> 00:12:57.580
Anyway, seven times nine.

00:12:57.580 --> 00:12:59.320
We're going to add another seven here.

00:12:59.320 --> 00:13:01.152
It's going to be sixty-three.

00:13:01.152 --> 00:13:04.830
I'll do it in the same color.

00:13:04.840 --> 00:13:08.350
All right, we're at our eight times tables.

00:13:08.360 --> 00:13:10.660
Eight times one is eight.

00:13:10.660 --> 00:13:12.520
Eight times two is sixteen.

00:13:12.520 --> 00:13:14.090
Twenty-four.

00:13:14.100 --> 00:13:15.690
Eight times three is twenty-four.

00:13:15.690 --> 00:13:18.300
And if we go to three times eight we should also see the twenty-four.

00:13:18.300 --> 00:13:19.500
Yep, it's there.

00:13:19.500 --> 00:13:21.110
These values are the same.

00:13:21.120 --> 00:13:22.800
So we're actually doing things twice.

00:13:22.800 --> 00:13:24.848
We're doing it when you do eight times three

00:13:24.848 --> 00:13:27.470
and we're doing it when we did three times eight.

00:13:27.472 --> 00:13:31.210
Let's see, eight times four, you're going to add eight to it-- thirty-two.

00:13:31.220 --> 00:13:32.480
Forty.

00:13:32.490 --> 00:13:34.690
Add another eight, forty-eight.

00:13:34.690 --> 00:13:37.270
Notice, eight times six, forty-eight.

00:13:37.270 --> 00:13:40.230
Six times eight, forty-eight.

00:13:40.240 --> 00:13:42.450
All right, eight times seven.

00:13:42.450 --> 00:13:45.860
Well, we already pointed that one out, that was fifty-six.

00:13:45.870 --> 00:13:48.200
Eight times eight, sixty-four.

00:13:48.200 --> 00:13:52.010
Eight times nine, add eight to this, is seventy-two.

00:13:52.010 --> 00:13:54.640
Now we're at the nine times tables.

00:13:54.650 --> 00:13:57.260
I'm running out of colors.

00:13:57.260 --> 00:13:59.520
Maybe I'll reuse a color or two.

00:13:59.530 --> 00:14:01.100
I'll use the blue again.

00:14:01.110 --> 00:14:03.280
Nine times one is nine.

00:14:03.280 --> 00:14:06.700
Nine times two, eighteen nine times three-- we actually know all of these.

00:14:06.710 --> 00:14:08.097
We could look it up in the rest of the table

00:14:08.097 --> 00:14:11.290
because nine times three is the same thing as three times nine.

00:14:11.290 --> 00:14:13.280
It's twenty-seven.

00:14:13.280 --> 00:14:14.500
Add nine to that.

00:14:14.500 --> 00:14:18.380
Twenty-seven plus nine is thirty-six.

00:14:18.390 --> 00:14:21.520
Thirty-six plus nine is forty-five.

00:14:21.530 --> 00:14:25.331
Notice, every time you add nine, you go almost up by ten,

00:14:25.331 --> 00:14:26.219
but one less than that.

00:14:26.219 --> 00:14:29.970
So up by ten would be forty-six, and then one less than that is forty-five.

00:14:29.970 --> 00:14:32.647
But anyway, notice, the ones--

00:14:32.647 --> 00:14:33.880
well, I'll talk more about it in the future.

00:14:33.890 --> 00:14:37.510
But we go from a nine, eight, seven, six, five on this digit,

00:14:37.520 --> 00:14:38.835
on the second digit.

00:14:38.835 --> 00:14:42.510
And on this digit here you go one, two, three, four.

00:14:42.510 --> 00:14:44.010
So it's an interesting pattern.

00:14:44.020 --> 00:14:47.240
Another interesting pattern is the digits will add up to nine.

00:14:47.250 --> 00:14:49.270
Three plus six is nine, two plus seven is nine.

00:14:49.270 --> 00:14:50.831
We'll talk more about that in the future

00:14:50.831 --> 00:14:52.620
and maybe prove that to you.

00:14:52.630 --> 00:14:56.340
Nine times six, fifty-four.

00:14:56.350 --> 00:14:58.150
That was this one as well.

00:14:58.150 --> 00:15:01.720
Nine times seven, sixty-three.

00:15:01.730 --> 00:15:03.850
Nine times eight, seventy-two.

00:15:03.860 --> 00:15:05.910
Nine times nine is eighty-one.

00:15:05.910 --> 00:15:07.030
I don't know if you can see that.

00:15:07.040 --> 00:15:08.360
Eighty-one.

00:15:08.370 --> 00:15:09.480
There you go.

00:15:09.480 --> 00:15:11.080
Now, I could keep going.

00:15:11.080 --> 00:15:13.780
Actually, I should keep going.

00:15:13.780 --> 00:15:17.525
Well, I realize this video is already pretty long.

00:15:17.525 --> 00:15:19.316
I want you to memorize this right now

00:15:19.316 --> 00:15:21.200
because this is going to get you pretty far.

00:15:21.210 --> 00:15:25.542
In the next video I'm going to do the times tables past nine.

00:15:25.542 --> 00:15:26.960
See you soon!