Hi guys, do you know how to transform a fraction into a decimal and a decimal into a percentage and do you know how to do the inverse of all of this? If you don't know, you're in the right place, welcome to my channel, I'm Gis and in this class I'm going to explain the transformation of a fraction in decimal number, decimal in percentage and vice versa so if you have doubts and want to learn, come with me. .
. It is very important that you know how to transform a fractional number into a decimal number because in several exercises out there that we work require this transformation right so I'm going to teach you today but before that I'm going to ask you two things, subscribe to the gis channel if you're not subscribed yet and leave me a thumbs up ok. So in this first part we are going to do what we are going to transform a fraction, right, which is a fractional number into a decimal, okay, just remember that here we are working with an exact decimal, okay, now in case you want to know how to do it with a decimal that It's not exactly what the periodic decimals are, okay, I invite you to watch the class that I'm going to leave here on the card, okay, it's explained to you how to do a decimal in a generating fraction, okay.
So how do I have the fraction 3 quarters here, how do I transform it into a decimal, most students think that I have to divide the largest number by the smallest number and that's not the case folks, the rule is divide the numerator by the independent denominator who is the largest, okay, so you don't need to think wrong like most people think, okay, so who is the numerator, do you remember who the numerator of a fraction is? numerator is the number at the top, okay, and the denominator is the number at the bottom, think like this, at the bottom, okay, so the numerator is this and the denominator is four, so for me to transform this fraction 3 quarters into a decimal number, I just need to divide three by four so here, dividing here 3 by 4 look what will happen three is smaller than four so that's why most students think they always have to divide take the largest one here the smallest one here, but you won't go wrong but that's ok, you understand now, right, always numerator through the denominator three is less than four which I have to do so put that 0 here and a 0 here in the dividend, that's not what I had to do because even if you do that If you missed the Gis class in which I explained division with decimal numbers in detail, I invite you to watch this class and I will also leave it here for you, ok. So now it's 30 divided into four 30 divided into four is seven times seven times four is 28 and here we have two left, right now as there is already a comma here I 'm going to put a 0 here in this remainder so now I have five times 5 x 4 are 20 and the remainder 0, so three quarters which is our fraction is the same thing as the decimal number 0.
75 or you could say it correctly, right? 75 hundredths, right? This one here, 12/5, we're actually going to divide the numerator by the denominator, I'm going to divide 12 by 5, look, 12 I'm going to divide by 5, okay, 12 can be divided by 5, right, two times two times five are 10 and two x five are 10 and there are 2 left and now the rest is smaller, right?
I have these two units, I'm going to transform them into 20 tenths, put a 0 here and here's a comma, right? And then there are four times 4 x 5 are 20 with the remainder zero so my fraction 12/5 is equivalent to the decimal 2. 4 and 2.
4 I read it, right, the correct way to read it is two integers and 4 tenths remember folks when we have two places to the right of the decimal point they are hundredths when I have a place to the right of the decimal point we have tenths, okay. Look at this other one here 7/20ths so this is the fraction to transform it into a decimal so I'm going to divide 7 by 20 and then 7 can't be divided by 20, isn't that what we do, put the zero because it turns into 70 tenths, okay? and then there will be zero comma here so now 70 / 20 are 3, 3 x20 are 60, 10 remains, now I add another 0 here and it will be five, 5 x 20= 100, zero remainder remains here, so the fraction 7/20 is equivalent to the decimal 0.
35 which I read as 35 hundredths because I have two decimal places here, ok, do you understand? Look at the last one here, now this one here our denominator is 100, so when I have denominators that are multiples of 10 if it is 10, 100, 1000, 10 thousand I always go read it like this, in this case as it is 100 I read it because it is one hundredths, so here I have 18 hundredths, in this case I wouldn't even need to do the division because I know there are 18 hundredths look here, here it is not 35 hundredths there are no two places on the right of the decimal point here it is not 75 hundredths there are two places to the right of the decimal point, so when I looked here 18 hundredths I know that it will be two places to the right of the decimal point so it will be 0. 18 it will be in doubt let's do the division calculation So here I'm going to divide, let me do it in black, right, 18 I'm going to divide into 100 , and now we can't divide, right ?
once, 1 x 100 = 100, 80 remains, I add another 0 and there are eight times 8 x 100 = 800 with the remainder zero. What happened there was 0. 18 which is what we had said, so here zero and let's do it in black, right Gis 0.
18 which is our 18 hundredths oh, 18 hundredths, until it was ready we just had to hit the eye, right, and write in decimal form , so just remember that here I'm working with an exact decimal transforming a fraction into an exact decimal, okay? Now we're going to do it the other way around, we're going to transform an exact decimal into a fractional number, shall we? Guys, now we're going to transform the decimal number into a fraction, how am I going to do it?
It's simple, the first thing I'm going to look at is this number here, it has how many decimal places, how am I going to know how many decimal places this 0 is representing 0 units, isn't it? this 8 is representing 8 tenths, right then it means that I have a decimal place here, just look here you already know a decimal place when I have a decimal place there in the decimal number it means that my denominator of the fraction it will be the right 10 and whoever will be in the numerator the numerator will be or eight because here it is zero units so it will not interfere with anything, so it means that eight tenths is equivalent to the decimal number that I have here which is 8 tenths the reading of it, and then we can simplify this fraction here by some number and it gives, I can find a number that divides 8 and 10 which is 2, what is it that gives 8 divided by 2, 8 / 2 are 4 and 10 / 2 is 5, so guys, if you want to think about it, but that means that if I divide four by five and eight by 10 it will give this result, you know why, it will give the same result because these fractions that I wrote here are called equivalent fractions so they have the same result, right? This one here guys, what do I have there, I have 0 units, I have here 5 tenths and two hundredths, isn't that right, I have how many decimal places, I always look to the right of the decimal point, here, right, my hand here, so I have two decimal places ok, so what do I already know if I have two decimal places that my denominator will now be 100 ok because I'm talking with two decimal places I have two zeros here in the denominator ok and who will be in the numerator in the numerator will be 52 because here it is zero units it will not interfere with anything, so the fraction 52 hundredths is this decimal number here and then I ask you, can you simplify this fraction here, can we simplify this fraction here 52 gives 4, then 4 if I divide 52 by 4 I will have 13 and if I divide 100 by 4 I will have 25 so it means that the fraction 13/25ths is a fraction equivalent to 52 hundredths and if you want there take the real test and see if everything is ok, just divide 13 by 25 who you will find you will find 0.
52 which is our 52 hundredths remember that the equivalent fractions have the same result, ok here 2 ,1 which are two integers because here I have two units and a tenth, how am I going to write it in the form of a fraction? I'm going to look at how many numbers I have in the decimal place, one in the decimal part to the right of the decimal point, right? decimal place so my denominator is 10 and whoever is the numerator is just the 1 like I put in all the others, here it was 52 I put 52 here it was the 8 I put 8 and now I only put the 1, no, right people, because now I have two units here so you have to put two units too, okay, it will become 21 because right here I didn't put this zero here because it was zero it won't interfere right and then it will work 21 tenths will return to 2.
1 divide o, take 21 divide by 10 are 2 x 10 are 20 left over 1 I put the comma and the 0 which will give once o which will give remainder zero o 2, 1 two integers and one tenths ok? And here in this last one, you must already be answering, for me it's not how many decimal places I have here, look, one two three, so my denominator will be one thousand because there are 3 zeros there, and whoever goes in the numerator is 85 because here it is zero here It's zero , it wo n't interfere and then I can find a fraction equivalent to it, right ? If you divide 17 by 200 you will get this number here which is 85 thousandths ok guys now what are we going to do to transform a decimal number into a percentage, shall we?
Guys, now we're going to transform a decimal number to a percentage, decimal to a percentage because you've already learned how to transform from a fraction to a decimal, you've already seen it from a decimal to a fraction, now we're going to go from a decimal to a percentage and finally from a percentage to a decimal, which is here. OK? So how do I transform the decimal number into a percentage, it's very easy, just multiply by 100, you'll take this number here and multiply by 100, if you've already watched that class in which I explained how to transform by multiply by 10 by 100 by 1000 by practical mode without setting up the algorithm, so if you haven't watched it, I'll leave it here for you, the card is ok, so when I multiply by numbers that are multiples of 10, the decimal point walks, moves, jumps however you want, speak to the right, how many spaces Gis , how many zeros are there in the number I'm multiplying, like there I'm multiplying by 100 she's going to jump two spaces to the right so where was she here oh she was there next to the zero so she's going to take one step two steps where she goes stay between 8 and 5, so my answer here will be 8.
5%, right, look how simple it is to turn a decimal number into a percentage and now this one will be multiplied by 100 so you're already answering there, right, and skip two squares one two it will be between 8 and 6 so I have 28. 6% and don't forget guys we have to put the symbol to represent the percentage ok and here how it will be here I will multiply by 100 and So there, if I use the decimal point to skip two places, it will be missing, so what do I do when there are missing digits, I put 0, so hey, she's here, she skipped one, there's no one else, so that means I go there and add a 0, right? it skipped two, so that means it will be 430%, let's test it again in case you didn't understand very well, the number was 4.
3, that wasn't it, let's multiply it by 100, the decimal point will move to the right, so it skipped one place and it got here, no there were more digits so I went there and put a 0 again, a two then it would be here like here then it will make the number whole I don't need to write the comma anymore but if you want to write it you could put it as 430. 0 but here it is very common We find this here, we always find the whole number like this without the decimal point, but no problem, okay? So look how easy it is to transform a decimal number into a percentage, just multiply by 100 and I can't forget to put the percentage symbol right now how do I transform a number that is already a percentage into a decimal, well what do we know?
of the percentage, I know that this symbol here means per 100, so I know that 12% is the same thing as 12 divided by 100, that's not it, and then here I have a fraction like that, now I put it in decimal, I divide twelve by 100 when I divide by 100 is the opposite process if I multiplied by without the comma it went to the right if I divide by without the comma it goes to the left so here it will be 0. 12 because as twelve is a whole number the comma is here, it wasn't here in the 2, then she jumped, one two, she stayed here and then I added the number 0, so it's very easy to do, there are two decimal places, here it is 100, very easy. And this one, so you can do it in your head, 90% is the same thing as 90 over 100, divide 90 by 100 then the comma will jump two places which will give 0.
90 but I need to write that 0 here at the end After 9, I can't just write , hey, the ink ran out, or just 0. 9, you don't need to write this zero here, I can omit it, okay. And lastly here so 21 percent I have 21 / 100 and 21 / 100 is the same thing as the decimal 0.
21 that the comma would be here look, it skipped one two it comes after the zero between 2 and 0 one two places so I have 0. 21. Hey guys, so this class was a summary for you because when we study percentages, the concept of percentage will use many transformations from decimal number to fraction, from fraction to percentage, in short, there will be a lot of these relationships here, so that's why you need to Watch this class so you can perform well in the percentage class, ok?
And if you liked the class I'm going to ask you two things like I already asked at the beginning of the class, subscribe to Gis's channel if you're not subscribed and leave me a thumbs up, and see you in the next class. . .
