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00:00I don't know what multiplication is. I wish someone could help me out.
00:13Whoa! I know you! You're Marco the Pencil!
00:18I am Marco the Pencil! And let me tell you, multiplication is one of the coolest things you will ever learn!
00:25It's a lot like having your own magic show!
00:28Really?
00:29Sure! Suppose you have a few of something. With a little multiplication, you can have many more.
00:38How do you do that?
00:39You're going to learn, my young friend. You are going to learn.
00:43I like magic tricks, but multiplication sounds complicated.
00:48It's not. It's really quite simple. I'll teach you.
00:52First, do you know what multiplication is all about?
00:56Not really.
00:57Multiplication is a quick and powerful way of adding the same number over and over again.
01:03If you can add, and I know you can, then you can certainly learn to multiply.
01:10Now, let me show you how multiplication works.
01:14Suppose you have three guitars.
01:17Ooh, I like the way that one sounds.
01:20Me too!
01:23Now, imagine you have five groups of three guitars.
01:29Whoa, Marco, that's a lot of guitars. How many are there anyway?
01:34Well, you could add three plus three plus three plus three plus three.
01:41Which gives you fifteen.
01:43But that's so slow.
01:45I'd rather be fast.
01:47I thought so. And that's where multiplication gives you power.
01:52What we actually have are one, two, three, four, five groups of three guitars.
01:58Three five times, or three times five, equals fifteen.
02:04Notice that this sign means times, and it shows that you are multiplying.
02:10You can also write the problem this way.
02:13Three times five equals fifteen.
02:18Well, the power of multiplication is that it takes something slow,
02:22like adding the threes one set at a time,
02:26and ba-da-bing!
02:28It makes the process faster in one step.
02:34Are you getting the power of multiplication?
02:37Loud and clear.
02:38Magnifico.
02:45The numbers in a multiplication problem have special names.
02:49The numbers we are multiplying are called factors.
02:53And the answer is called the product.
02:56You can remember this quite easily because you go to stores to buy products, right?
03:01And where are those products often made?
03:04Factories. That sounds kind of like factors.
03:08Oh, you're good. You, you're good.
03:11So, we multiply the factors in this factory part of the equation to get our product, or answer.
03:18Smart boy. I like it the way you think.
03:21Now, I know a great way to practice multiplication and really experience what it's all about.
03:27I'm going to need some pennies.
03:31Did somebody call for us?
03:33Actually, yes, but I need even more pennies.
03:37So, how many of us do you need?
03:40Could I perhaps get twelve pennies?
03:43Okay, we'll just multiply ourselves times six.
03:49Is this better?
03:50Certainly. Two times six is twelve.
03:54But I was hoping to get some real pennies.
03:57We're not real? Oh, no.
04:04Let's work with these real pennies.
04:07You can get your own pennies and easily practice this yourself.
04:11Take six groups of four pennies.
04:14To know how many pennies you have, you could count them.
04:181, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24.
04:35But if you know your multiplication facts, a much easier way is to say four times six equals twenty-four.
04:43That is much better. Now I know why it's important to learn my multiplication facts.
04:49It can save me a lot of time in the long run.
04:52Right. Another great thing about multiplication is that the order in which you multiply the factors does not matter.
05:00We can change the order of the factors and presto digio!
05:05The product does not change. Let me show you why.
05:09This shows the multiplication problem four times six.
05:13And if we move it around like so, it now shows the multiplication problem six times four.
05:20But we still have the same number of pennies, twenty-four.
05:24Oh, I understand.
05:31Let me show you some other neat tricks with multiplication.
05:35When you multiply a number by one, the answer is always that same number.
05:41Four times one equals four.
05:44Six times one equals six.
05:47Eight times one equals eight.
05:50Fifty times one equals, you guessed it, fifty.
05:55That's easy to understand. And since you can switch the places of the factors,
06:00I'll bet you can multiply one times any number and your answer will always be that number.
06:06That's right. You're right.
06:09Here's another trick.
06:11When you multiply by zero, you always get zero.
06:16Any number times zero always equals zero.
06:19That just makes sense, Marco.
06:21Marco, if you have zero groups of something, you don't have anything.
06:25And if you swap that around, no matter how many times you add zero to zero, you'll always get zero.
06:32Perfecto.
06:34Now, how do people get good at multiplying?
06:37Uh, they could use a calculator?
06:40Well, it's not always convenient to use a calculator.
06:44Smart people, and smart pencils for that matter,
06:48memorize their basic multiplication facts from one times one all the way up to nine times nine.
06:55Some people even like to memorize all the way through the twelves.
07:00How am I going to do that, Marco?
07:03The same way you get through Carnegie Hall, kid.
07:06Practice.
07:08Huh?
07:09Never mind.
07:10One easy way to memorize your multiplication facts is with a beat.
07:17You can also practice skip counting.
07:20Whatever you do, practice makes perfect.
07:28I want to show you a trick that you can use to help you learn multiplying by nine.
07:33Can you give me a hand?
07:35I don't seem to have any at the moment.
07:38Actually, I need two hands.
07:41To multiply any number by nine, look at your ten fingers, palms facing you.
07:47Your fingers are numbered this way.
07:50Count from the left until you reach the number you want to multiply by nine and bend down that finger.
07:58Count the fingers to the left of the bent finger for the number that goes in the tens place.
08:04The fingers to the right of the bent finger give you the number in the ones place.
08:10For example, to calculate three times nine, bend down the third finger.
08:15There are two fingers to the left of the bend and seven fingers to the right.
08:21So the answer is twenty-seven.
08:26To find the answer to four times nine, bend down the fourth finger.
08:31There are three fingers to the left of the bend and six fingers to the right.
08:37Four times nine is thirty-six.
08:40Wow, I love that trick.
08:42It only works when multiplying by the nines, but you must admit it's pretty handy.
08:55Hey Marco, can you show me some more tricks?
08:58No.
08:59Please?
09:00Okie dokie.
09:01Actually, this one is so easy, it's a little embarrassing.
09:05It's a trick for multiplying by ten.
09:08To multiply any number by ten, simply write it down and then presto!
09:13Add a zero at the end.
09:16You see?
09:17Four times ten equals forty.
09:20And sixty-five times ten equals six hundred fifty.
09:25And three hundred seventy-two times ten equals three thousand seven hundred twenty.
09:31Super!
09:33I wish there was some way for me to see all the facts I need to learn.
09:37You know, all at once.
09:39Your wish is my command.
09:41Watch and be amazed as I turn this ordinary picnic table into a times table.
09:49Awesome!
09:50We can find the product of any two factors by looking at this table.
09:55Six times eight equals forty-eight.
09:59Seven multiplied by nine is sixty-three.
10:04Let me try, Marco.
10:06Eight times four is thirty-two.
10:11I hope you've had a good time learning about multiplication with me.
10:15I sure have, Marco.
10:17Now it's time for me to go practice my times tables.
10:23That's a great idea.
10:25You might even want to time yourself.