Chapter2 :Arithmetic operations

Hi everyone! Today, we will be talking about the first of the four operators: addition. You use addition when you add up two or more things and put them together into a larger thing. The addition symbol, also called a plus sign, looks like a cross. So when you say you want to add 1 and 2, you write the expression 1 + 2. Let’s look at this idea with movements. How would we find the answer to 1 + 2? Let’s remember the number line in the last two videos. Because 1 and 2 are both positive numbers, we will only be traveling to the right. First, for number 1, let’s take one step to the right. Here, when you add, the only thing you have to do is not go back to zero, your starting point. Instead, for the number two, take two steps to the right from the place you are standing right now. Then, count the distance you traveled from your original spot, zero. One, two, three! So now you know that the answer is three! Let’s look at another example: 4+ 2. For number 4, we take four steps to the right, and from here, we take two steps to the right again. Okay, so how far are we from zero? One, two, three, four, five, six! We are 6 steps away, so the answer to 4 plus 2 is six.

Hi everyone! Today, we will be talking about the second of the four operators; Subtraction. In contrast to addition, we use subtraction when we want to remove something, and the subtraction symbol, also called a minus sign, looks like a dash, just like the negative numbers. So when you say you want to subtract 1 from 2, you say 2-1. Let’s look at this idea with movements. How would we find the answer to 2-1? You do the exact same thing with addition. First, for number 2, let’s take one step to the right. And from here, just like when you added, the only thing you have to do is not return back to zero, your starting position. Instead, think of the dash in front of second number as a minus sign for a negative number, so -1 in our example, and take 1 step to the left. Then, count the distance you traveled from your original spot zero. One! So now you know that the answer is one! Let’s look at another example: 4 - 2. For number 4, we take four steps to the right, and from here, we take two steps to the left because we think of the subtraction sign as a negative sign for two. Okay, so how far are we from zero? One, two! We are 2 steps away, so the answer to 4 minus 2 is 2.

Hi everyone! Today, we will be talking about the third of the four operators: Multiplication. We use multiplication when we repeatedly add a number. For example, when we say we multiply 2 by 3, this means that we add the number two three times, or, we can also say that we add the number three two times. Here, the multiplication symbol, or the times symbol, looks like an x, so we write 2 multiplied by 3, or 2 times 3, as this: 2 * 3. But how do we find the answer to this? First, for the number two, think of two different movements that you like. I will go with these two: a roll and a clap. Now, because we are adding two three times, we repeat these movements three times. roll, clap, roll, clap, roll, clap. How many movements did we make in total? Six! So the answer for 2 * 3 is 6. Let’s try another example. Five times two. Think of five movements. I will go with a roll, a right foot stomp, a left foot stomp, a clap, and a hop. Now, because we’re adding five two times, we will be repeating this little dance two times. How many movements did we make in total? One, two, three, four, five, six, seven, eight, nine, ten! So the answer for 5 * 2 is ten.

Hi everyone! Today, we will be talking about the last of the four operators: Division. Division, in an easy way, is a way to see how many times a number can be broken down into another number. For example, If you want to break down the number four by two, then you say you divide four by two and write it as 4 ./. 2. The division symbol here is the one that looks like two dots separated by a dash in the middle. So how do we find the answer to this? How many times can you break the number four by two? Grab a partner, and ask the partner to clap four times. At the same time, you will be in charge of the number two. While your partner claps four times, you will count each clap in two’s. Like this: . how many times did you have to say the phrase “one, two’?. Correct, two times. So we know that four can be broken down into two a total of two times. Let’s try another example: six divided by three. So now your partner will be clapping six times while you count them in three’s. : _______. how many times did you have to say the phrase “one, two, three’?. Correct, you said it two times, so the answer to 6 divided by 3 is two.

Hi everyone! Today, we will be talking about parenthesis. You may have seen a set of curves that looks like this in books, and the math version of the parenthesis looks the same. You use them when you want to let people know that the part in the parenthesis must be figured out first. For example, in (4+3)-1, we need to add 4 and 3 first before we subtract 1 from the answer. To practice this, let’s play a little game. I will give you a set of movements to dance, but I’m going to say paranthesis before one move. When you dance, you have to do the move in the parenthesis first before anything else! For example, if I say twirl, hop, parenthesis clap, you have to clap, then twirl and hop. Got it? Okay. This is the first command: stomp, roll, parenthesis slide, hop! Ready? go! Perfect. Now, let’s do another one. Shoulders, clap, parenthesis roll, stomp, stomp! Ready, go! You got it! Okay, but what if there are real numbers? Let’s go back to the example (4 + 3) -1. We know that we need to add four and three first. Going back to the number line, we will be travelling right four steps, and then take three more steps to the right. Then, from here, we just do the subtraction like we did before. If you remember, we thought of the minus sign as a negative sign. So in this example, we have the number negative one, and so we travel to the left one step. Now, how far away are we from zero? One, two, three, four, five, six! So the answer to (4 + 3) -1 is six.

Hi everyone! So in the last video, we learned that anything with the parenthesis should be done first. But what if there is an problem like this: (3 + 4)-2*2? What do we do first after adding three and four? Subtract or multiply? There is a rule for this: First, if there is a parenthesis, you always do the things inside first. Second, if there is a multiplication or a division sign, you do them next. Last, if you see an addition or a subtraction sign, you do them last. Let’s look back at the example (3 + 4)-2*3. Here, our first step will be to add three and four because they are inside the parenthesis. So we will be traveling four steps to the right, and then another three steps to the right. How far are we away from zero? One, two, three, four, five, six, seven! So the answer to the part inside the parenthesis is seven. Now, we see a multiplication sign! This means that our next step is two multiply the two numbers next to the sign: 2 and three. Think of two movements. I’ll go with slide clap. Let’s repeat this three times. slide, clap, slide, clap, slide, clap. How many movements did we make? One, two, three, four, five, six! So the answer is six. Now, we see a subtraction sign. What do we subtract from what? First, let’s look at the left of the sign. We have the parenthesis, which we found the answer was seven. Next, to the right of the sign, we have the multiplication expression, which we found the answer was six. Okay, so our new problem is 7-6! We take seven steps to the right, then 6 six steps to the left. How far are we away from zero? One! So the final answer to this big problem is one. Let’s try another example. 4 ./. (1+1) + 3. Here, our first step will be to add one and one because they are inside the parenthesis. So we will be traveling one step to the right, and then another step to the right. How far are we away from zero? One, two! So the answer to the part inside the parenthesis is two. Now, we see a division sign! This means that our next step is to divide four, the number on the left of the sign, by 2, since that is what we got as the answer for the part inside the parenthesis. This time, let’s try the division without a partner. While you clap four times, count them by two’s with your mouth. One, two, one, two. How many times did you say “one, two?”. Correct! two times, so the answer to the division is two. Now, we see a plus sign. What two numbers do we add? First, let’s look at the left of the sign. We have the parenthesis, and then division, which we already solved and got the answer of two. Next, to the right of the sign, we have 3. Okay, so our new problem is 2+3! We take two steps to the right, then another three steps to the right. How far are we away from zero? One, two, three, four, five! So the final answer to this big problem is five.