TenMarks teaches you how you can divide whole numbers.
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This track covers the division of whole numbers and we will learn about the basics of division as well. There are two problems. The first problem is for us to separate 343 into 7 equal parts. To separate a number into a number of equal parts, we fundamentally divide and we can indicate division in different ways. The symbol for division is “÷”. We can also indicate a division by a division box or we can do it by a division bar, so we can do 343/7, this works as well. This would be 343÷7. This would be 7v343 or we can even do 343/7. They all mean the same thing. Each of these expressions means a division. In order to represent this, here’s what we do. In order to divide 342 by 7, let’s use the long division method which is the following way. We try and find out 7 times what will give me a number less than 34, so 7×4 gives me 28. I subtract 28 from 34 which gives me 6. I copy this number down, the next digit down which gives me 63. Now, 7 times what will give me 63? Well, 7×9 will give me 63 and I’m left with no remainder. The answer of dividing 343 to 7 equal pieces which means each piece is 49, each part is 49. 343÷7, I can represent it this way. I can represent it this way and this way divided by 7 equals 49. Let’s do the real problem which is for us to evaluate and check the number 3456 when divided by 7. We will use the long division method and we will divide 3456÷7. In order to do a long division method, we draw the division box. We write the dividend 3456. The number which is being divided is called the dividend. It is also always dividend divided by divisor gives you a quotient. These are just terms to use plus a remainder. Key to remember is you give the dividend on top, divisor on the bottom gives you the quotient. In this case, the dividend is 3456, the divisor is 7 and we need to find the quotient. The dividend is always placed inside the division box, the divisor is outside to the left and the quotient is computed on the top. How do we do this? First, we try and see what number I can multiply 7 by to get the value of 34 or less than 34. 34 is not divisible by 7, so if I multiply it by 4, 7×4 is 28 which gives me a remainder 34-28 is 6. I bring 5 down. 7 nines are 63 which brings a remainder of 2 and that brings 6 down. 7 threes are 21 which give me a remainder of 5 and there’s nothing more to bring down. So, what we are left with is the divisor is 7, the quotient is 493 and the remainder is 5. The answer to 3456÷7=493 with a remainder of 5. That’s the answer. There are ways for us to check if this is the answer. If this was the correct answer then what I would get is I can place 493 which is the quotient. I place 493, I multiply this by the divisor and I get the answer which is 3451. I add to this the remainder and this should give me the number that I started with which was 3456 which means I got the answer correct. Quickly recapping what we’ve learned. When we are dividing whole number, there are different ways to represent division. I can use the division sign. I can use the division box, the over numerator denominator principle or I can use a slash; they all mean the same thing. In order for us to divide, I put the dividend inside the division box. The divisor goes on the outside. The quotient is what the answer is and the remainder is what is left when we are done dividing. The way you divide is you look at 7×4, it gives you 28. I take the first two digits. 34-28 gives me 6. I copy five down, 65, we start all over again. 7×9=63, remainder is 2. I copy 6 down, 7×3 is 21. It gives me a remainder of 5. If there are no more digits to copy, I can simply say that 3456÷7 gives us the quotient which is 493 with a remainder of 5. I can double check this by multiplying the quotient with the divisor, taking the answer and adding the remainder to it and it should bring us to the number we started with which in this case would be true because that’s the number we started with.