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Math 7 - Module 2B - Lesson 13 Day 1

Added Apr 25, 2021 •

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decimals message IRL in RL in real life money money and what did I say when you got where we guys are screwing around 4 if you don't have something to write with go to mail staff walk around before we start class would you guys do decimals in real life money money is the most common way we use decimals is there any other thing we might use decimals in for real someone said measuring I will put that actually in both so let's go fractions and in between fractions and we actually measure in both fractions and decimals we measure things in half inch quarter inch but when we use the metric system that's why we are not like the rest of the world we're like the only country that doesn't standardized measurements in the metric system meters to centimeters if use meters in centimeters most of the time we use decimals or fractions we will use inch inch and feet so let's go measurement for both purple fractions I like that portion portions of objects when we use fractions for portions of objects cuz if we go to let's say a diner and we're feeling extra hungry for dessert a whole pie for yourself you get a half a slice of pie get a quarter of a pie portion of objects slices of pie or measuring wood or carpet measuring wood Carpenter cuz you know it over here we measure everything and you know eating fractions of inches are fractions of feet so car that's nuts carb and tree was a good one here's another one that someone said they said food what do you mean food and you hit the answer so I said food like slice of pie and this person is a fool what do you mean food like cooking you hit another example what are even thinking about it cooking cuz you know you need a half a cup of sugar in a IMEI with me sugar to make Kool-Aid I love Michael. I used to like playing but I got tired of pain so yes I can I get pissed off and Costco runs out of my my my tropical punch they have giant thing and we can't see it that the giant tub of left at 10 cuz yeah that's what I had a play that out so I don't think who doesn't like Kool-Aid shame on you don't drink airplane water drinking plain water let me fix roll hey no I don't mess with the Crystal Light I don't mess with the other the country time lemonade can't this weird Valles that make real lemonade I need sugar how much sugar that's the whole thing you don't need to fault you don't need to follow the instructions those are suggested amount of sugar for your drink you can always put less that's why you use you put more and I'm out of here so these are examples of where we use decimals I can only think of money so we got we got all these we didn't think I like I said I got an example that's something I can't think of fractions three different examples of fractions but decimals alright so can anybody besides money money is there another example where we use decimal I'm stuck too that's all that came to my mind if you come up with something let me know in the chat so let's look at this next example to what value what is the value of the number 2.25 what does that mean we'll go with that in a second to think about that how can this number be written as a fraction or mixed number so first what does 2.25 mean what is 2.25 mean what's tannin in chat good all right stop stop I'm going to hold off on your response in a second I like it yours or yours is perfect for the second part it is half right to wait wait two and a half weight as she goes for both of the measurements so that you can measure your so I'm going to go back wait length and all that stuff measurement carpentry those are all good .25 so we remember we went over this in the Mazda the first module module at 1 a.m. I think one 2.25 is the lazy way for us to read decimal does anybody remember the correct way to read the decimal I'll take all the weight length odometer 2.25 the lazy way to reading it how do you read it correctly how do you read the decimal part correctly it's .25 is the laser it don't even say point to buy what is the best thing knowing hardly ever read it correctly everyone would read it two points unless you're a scientist but even some scientists are still lazy there it is 2.25 what is the correct way of reading 2.25 anybody decimal places yes to an but someone said you forgot to. To know not to. But I like it another person before you before you type it and said that to an but they they forgot the spacing of the name all right let's go with the spacing of the name so you would get almost full credit for that too and spacing remember decimal places have names so some number in the front right here we don't care what the number in front that's the ones I just put that there so this is the one and I remember ones tens hundreds thousands of those works but when go backwards from the decimal going the other way just like a number line ones ones work starts ones and then next to the ones you got tens but when you go the other way the fur can you start with the letter b i t h s after tens it would be hundreds but after this it would be hundreds on hundreds whatever the next month after hundred on this I would be 1000 mm spot and then this might would be thousand thousand 10000 hundred thousand million Tomatoes score for we just add THS in the back and it's going the other way for the decimal so you got to know the spot so you read it the number as is and you read the spot that is in so good both people said well the two and front represent two hole that is correct so that's the ones I got to hold these are all whole numbers how many whole numbers you got in a fight in the back and the next person said is a fraction but it's not a fraction is written as a decimal and that's how it ties into our lesson converting between fractions and decimals using equivalent fractions the same thing a fraction just reading the spot where it is so let's to hole what's rated as asset to + 25 + 259 + 5000 sorry to and 25000 let me know when it's off the screen please read the decimal and the thing is if you that's a whole number so that's just a to how can this number be written as a fraction or mixed number so remember a mixed number includes a whole number and a fraction so where is she this right here we can write it as an improper fraction and a second one that will do that in a bit but and 20 correction good on stop thank you for letting me know I just caught it when I was reading it one person got it too bad I might give away bonus points but I would if you know it's not that thank you for catching that good job you're too late next person 2500 thank you for correcting a good job cuz right here it's cuz I wrote thousands I had a brain fart as the last one that gets stuck in my head but you look at it how many decimal places are there to decimal place first decimal place second decimal place turn decimals 4th and so on so you read how many decimal places there are read the number first read ignore the decimal read it as 2525 and then how many decimal places you put that 2 + 2500 so for the fraction you just write a 25 and the hundredth part that's what you put it over there it is as a fraction and right here convert between fractions and decimals using equivalent fractions so first you write it read the decimal 25 read the space there you have a fraction next thing you do you simplify the fraction 25 over Latias good I got quite a few people that said that could have been simplify to 1/4 so this is equal to we simplify it Down 2 and 1/4 read it at in real life we wouldn't use 2 and 2,500 would use 2 and 1/4 by 2 and 1/4 1/4 is 1/4 is another way of saying 1/4 to 1/4 and someone said you had it one person wrote it as an improper fraction good you remember it we got to whole 4 * 2 is 8/8 + 1 is 9 you can write it as an improper fraction so these are all the different ways of writing 2.25 2 + 2500 is what we should read it that's another way to write it if we translate this into a mixed number 2 and 2500 same thing as an American version this way is the simplified version as a mixed number and then as an improper fraction 9/4 good job we already did that to get all the steps right here so be rewrite we already did that so that's all right here rewrite the fraction in its simplest form showing all the steps to use well that's come by here that was a this is a to we could say that's be right there so right there we did all the work all right so let's go look at the next one which what is the value of .025 now that's the Thousand spot so this right here is 2 and 25 so we don't read the zero in front as there was a placeholder it just tells us how many decimal places we have so we just read it as a number 25,000 the difference two decimal places versus three decimal places this so red star test I'm going to bring it up now these are some simple questions that you will get on your rent Star Tours you know if they give you a sentence choose the right number if they give you the number of choose the right sentence form of suppose you're going to be easy questions on the rain start if you get I'm everybody's been start slightly different but easy questions don't knowing the right here that you and 25 no one's going to get wrong you won't mess up in your it's the decimal place name so get that right for the what when is the rent at the Red Run start is the first week of May for not next week but the week after we're going to do the ren star for Math and English again I got a bunch of sides what size just do it get it done see what you've learned feel happy about it yes how can this number be written as a mixed number so same thing right here let's change is to a mixed number so too and just read the number 25 and a t h s part is put that as your denominator no at least your English is good you wrote mr. Nanny mask is to to complicated but you corrective the too you know how did the difference between see I didn't even know the difference between t o and t o o I just need the difference between t o and t w o triple D part D and Part B is telling you any time you have a fraction the fractions are at you're not fully done you always need to simplify your fraction 25 over a thousand we could / 25 so this becomes 2y let's write it out let's go simplify the fraction so we can't / 2 we could / you know how do you want to divide it alright fine you want to / 5 someone said I don't know how to divide by 25 but I can / 5 fine so let's look at only the fraction part just as the fraction 25 over 100 1,000 my fault when you simplify a fraction remember you divide the top and the Bottom by the same number divided by 5 divided by 5 25 / 5 5 1,000 / 5 200 but look at this we can still divided by 5 so let's / 5 again sometimes it's a different number sometimes you divide but whatever but you always take out what's in common here's another let me stop let me go back so 25 over thousand we divided by 5 and ended up with 5 / is the mistake a lot of guys make you focus back and what you did here anytime you simplify you want to ignore this part of he want to ignore it any time you write equal this and you know you got more work to do always temporarily ignore what you had before cuz you make a new problem for yourself think about it is my original problem 25 / 1000 can I change my problem by dividing of MiFi so instead of $25 thousand my problem is 5 / 200 you start over each time I think about simplifying is making a brand-new easier problem for yourself so you can't make a brand new problem anymore so 5/200 we can divide by 5 again you may so we 5 / 5 we get 120 / 540 so if we put this fraction back right here we merged this back together we put the whole number we have a mixed number all we do is put the whole number back and we can buy in the fractional be simplified back in there so a lot of people on the last test you gave me the fraction you did it this way but you forgot to put the whole number back that's why take away 0.0 yes I had to take away a point not a half a point half a point is like you forgot to put the negative sign back in when you forget a whole number I got to take it all right let's flip it over Adidas for you're going to do on your own let's read the instructions first use place values to convert each terminating decimal to a friend that means in a bit rewrite each fraction in its simplest so let's do the first one together what's up with the decimal 3 decimal places tens hundreds thousands so what you do is you take the decimal off so you rewrite it as to Jordan 18 218 and it's three decimal places three decimal places is over 1000 finish simplify this fraction and then do BCM I will give you a minute for each one so it's going to be 4 minutes starting now Mane first thing there's a couple of things we want you to do today but first things first know how to convert at least a fraction so for all these let's do the same thing for all of them so let's do the same thing for all of them first so this right here you got to know the decimal place this is two decimal places that's hundred hundreds so think about it however many decimal places there are add one to the work to list a list if we had two zeros think about if these were two zeros on the other side it's hungry at HHS. What I'm saying is I got three to put a one and put however many numbers are 21823 so30 thousand so however many whatever that is put on one. Write a one down so next one how many numbers are in the decimal place to 16 hundredths write down so forget the whole number for now write down a one first how many decimal places to so that's how many zeros you had that's hundred SO2 and 70/200 listen to the next one right Donna one how many spaces are in your decimal 12341 three four write your fraction number write the number down put it over this number five ten thousand so that's a no the way of doing it so someone you guys are my eyes fully forgot about the shortcut thank you for letting me know it's not a shortcut it's just another way of doing it let's go with that so if you don't know if you do not know your decimal number place names this was very good thing so right that'll one and however many decimal spots you have that's how many zeros you put in I got three decimal spots 123 218,000 decimal spots one and put the zeros in his place two decimal places 1600 that's a great shortcut thank you for letting me know alright so now we are here this right here if you got cheer on your test when I comes I would give you two and a half points each question is worth for you need to finish simplifying this show me some work to get three point total and shut and give me the correct answer. 4 point photo so the work is worth a little bit more and then the correct answer is worth your full for vacation so here's another way of looking at it instead of doing Division I do it on the next one. Show you two different ways so you want to simplify this fraction all right think of think of two numbers a cab number that that you can multiply both of these to get what I'm saying is 218 is 109 times to 1000 500 * 2 this is another way of doing it instead of division rewriting it as multiplication using the same number so hundred 9 * 2 is 218 2 * 2 is 1000 + in math when you multiply by the same number it's called multiplying by the same factor x 2 x 2 what's 2/2 good scene or I'm going one x one so this is called a factor when the numerator and denominator have the same Factory Connection Factor it out cross it out cuz 2/2 is a giant one cuz we're technically multiplying this fraction by 1 making equivalent fractions if you remember is multiplying by a special value of one some fraction of one so we can rewrite it as 109 / 500 and just to let you know there's nothing else we could divide or multiply by that's the same to get these right here to get you know simplified this is it a simplified form means you can't make the fraction look at smaller using Spotify music rewrite the fraction using smaller numbers make it look smaller than the division wait right here, look 16 100 off I know I could divide both of these by 4 Listen to over to 4/4 it's just a value of one that we either take out 16 divided 4 for 100 / 425 for over 25 that's it we can't divide anything else so that one is a test I'm not sure I got to go look I'll let you guys know that cuz we still got a couple of sections to go so we're good we're good all right next one right here so the two is a whole number Let's ignore the whole number and let's just look at 72 over 108, there and we'll come by so 72/100 let me rewrite this as something * 4 and I can put the number then a x in the front doesn't have to be in the back four times 4 times 4 times 25 gets me 100 I know that 4 * 18 it's just cuz I've known enough gets me 72 looking at this for over 4 is 1 that leaves me with 18 25th and again watch out on the last test so many guys remember we were doing them mixed numbers in 1 this is what some of you guys forgot you gave me you did this but you forgot the whole number so I had to take away a whole point don't lose that whole point so I put a, cuz I'm not there not equal I'm bringing back my home number 2 and 18/25 and I'm going to box that out for my answer that's what I would like you guys to do on your test show your work like this you don't have to do to make it go down show it in on top down 5 / 10000 5 * 1 / 5 * 2000 5/5 is a one it leaves me with lotus this I got a one up top this is not mm it's 1 mm if the answer was 2002-2018 the numerator yes good now you get it good good simplifying fractions you could either multiply or divide it's up to you write writing it as multiplication or writing is division does the same thing A1 all we're doing is dividing out of one or crossing out of when all right let's go look at example 3 good job what is a decimal what is a decimal another way to write fractions I like I like that that's one another thing we could say is it's a p it's not whole it's a piece a portion of a portion from a hole but that's just sounds like a fraction so I'm going to use the there textbook way this is kind of long but yeah I'm going to ride it decimals specify specify on the number line Chris-Craft thank you points on the number line by repeatedly here's a technical word subdividing intervals into text so what this means is like we're always cutting everything by 10 so I kind of get it but it's a 10 so any decimals anytime you have a fraction we're always cutting it into 10 pieces well anytime we have some hold is a whole unit we're going to cut it up into 10 pieces and then if we're going to take a frat a decimal of that each little piece gets cut into 10 pieces and then each little piece of that if talking about that just cut into 10 pieces we could keep on cutting and going to Infinity so notice the pink is 10 and out of that one it's a little blue one that's 10 and then within that one little piece is 10 and if we cut it up into that many so you got in a tenths hundreds and if I do a little purple and for all these you have a thousand little pieces in there and I will keep on cutting so decimals represent dividing by 10 is what it's saying why right here look at it all are decimals are base 10 100 is 10 tens of thousand is 110 ten thousand is 1010 everything's based on a tent that's why we can please make a nice little simple fraction out of it I 100 decimals and fractions a nice and boys converting it think about based on 10 all right decimal to relate use the meaning of Dessa to relate decimals 2 place value so place value goes up bye AMOLED full of pain so 0.1 is 1/10 examples 0.01 is 1/100 alright the next one so you list ten hundred one extra decimal place 1000 good and I'll do a couple more just so you could see so 0.0001 1 / 10000 and then the last us to Dunder hear 0.0001 01 1 / 100000 we could do a million but man I don't want to write that much so okay this is for you right here I'll let you write the number 3/100 as a decimal so this is a nice easy way to change fractions to decimals equivalent fraction over a hundred over 10 so try and make it we're going to get to that so let's 3 100 so we know we're going to have 100 how many decimal places decimal places so we know it's going to be some so let me ride it so look at how many zeros are are that's how many decimal places are R12 and then you put in number in your last spot and then right there that's a zero placeholder and we don't need this and that and it's just a bear by Buddy Play Store .03 it's a placeholder 3 100 let's look at this right here let's make an equal fraction over 100 so we can change it so it is 3/20 as a decimal so we know a fraction is over some value of x 10 what is a 2 * it's a base pain when I say base tennis tens hundred thousand and it was going to make it to the next closest thing 3/20 equals some number over 100 how does 20 become 100 thank you catch on quick so * 5 20 * 5 equals 100 to make an equal fraction to multiply the top and bottom the numerator denominator by the same value so they value of 1/3 * 5 1515 100 100 you know traunero we're not an eagleside hundredth you know is two decimal places I'm just you can put any letter you want that's how many decimal places you want and so you fit in your number into those that I can fit in both of my numbers in there where as this one right here only had one number she always if you just put in the bag and put in the and you got a zero in front as a placeholder but 15/100 only got two decimal places for my two numbers point 15 you just fill in the spaces let's look at this right here next 110 / 25 let's set it over 100 how many quarters make a dollar how many quarters make a dollar 4 * 4 what you do on the bottom of a fraction you do the top of a fraction you add by the same you add you multiply by the same number 4 / 4 4 4 is equal to what as a fraction what's 4/4 equal to one good what's 1 * anything the anything so look at this right here forget this 100 4/4 oz of one when you multiply anything by one that doesn't change the value 6 * 1 a million times 1 Anthony by one so it doesn't show when you multiply by a special fraction of one meaning it looked it's not just the one it's a fraction equal to 1 all we're doing is changing the way the fraction looks that's why it's equal so this 10/25 is equal to 40 / 100 you got a note 10/25 equals 4100 all we did was change the way it looks by multiplying it by value of one so we got to convert this to a decimal now that it's over 100 that's simple 100 hundredths has two decimal places it's a point something something but what does that something go in there for but that number their point 40 somebody did it a different way is different but look at this right here we should all wait we can always simplifier Friday if we got zeroes look at this right here x for another thing we could have done someone said do we need that 0 so you've actually done this big job so 40 / 100 should have been written as a simple version 4 / 10 that's still a fraction over a base 10 text is one decimal place hempz is one decimal place so that is equal to 2.4 Point form Point 40 are the same thing zeros in back of a number or just placeholders you don't need it so you point 40 is the same thing as point for you think is he change it to money that's $0.40 we're at that point for West Point for that's not $0.04 for cents looks like this this is 40.4 equals $0.40 .4 is also equal to 40 cents for sale 04 watch out for the money bit right there right this right here we're going to do this to different ways so 40 there's no number you can multiply to 40 to get 100 but we can X something else to get what's the four time what time is Left 4 * 24 * 5 + 200 1 over a hundred so we're always trying to get it something over 10 over 100 / thousand but if you can't someone setlist tri-five all right I'll show you let's say let's say you don't see how to get it over 100 first but you could get it over some type of 100 this is multiplication with a division 1 in a second so 8/40 let's go x 5 like someone said cuz they said that gets us 200 so we get 8 * 5 + 44 * 5 5 is 200 look at this how do you change 202 100 let's / 2 2040 / 220 20 / 2 100 sometimes you got to go one way or the other it's like Chutes and Ladders or the game of sorry do you go forward a couple steps. can I get the other card hunt you got to go back to steps so this right here 100 that's doesn't Arrow remember we got two decimal places just put this right here in 20 into the 2 decimal place Point 20 which yes you can write it as point to here's another way of doing it this way is for a little more advanced only because that's is called number sense understanding what numbers do what you trying to do we're trying to get it over you guys are always thinking 100 cuz that's that's for me it's already past 10 but how does huck E-40 become 10 / 4 and look at that can also divide 8 by 4 so instead of multiplying by 5 let's divide top and bottom by 4 that's still a value of one look at this 40 / 4 I have 10 a base number of 10/8 / 4 I got to 2/10 how do we change that into a decimal remember however many zeros are are on the bottom right there that's how many decimal place we got we got to decimal and we put the numerator in that decimal place point to hey look at that couple different ways of doing it dry the multiplier divide you want what you want the bottom to be like 10 hundred thousand we don't want to we want 200 we don't want 20 we could have made this literal we could have made this one we could have made this one at 10 but it would be a little bit harder that's why I'm going to go back right let's let's do this one let's go 3/20 how does 20 become 10 we / 2 the top by 220 divided by 2 is 10 but what's 3 / 2 what's half of 3 what's half of $3 yes $1 and $1 $0.50 1.5 * 1.50 but I don't need that so cuz it's a placeholder we only have the placeholder for money but 1.5 is after 3 we have this we got a decimal over that bad monkey that's not good now let's go review how to get rid of a decimal inside of a fraction so look at this right here so what's 1.5 / 10 rewrite this anytime you have a decimal to fraction and the one of them is not a dust put the decimal we're ghosts it would be 10.0 and I'll do and I'm doing extra steps this is all the things so if you remember to get rid of a decimal inside of a fraction you just move it over you look it over topping move it over the bottom E I move it one time is my new decimal place I move it over one time there's my new decimal place 15 over 100 hey look at that 15 / 100 same thing .15 look at this way making sometimes making it bigger is better than making it smaller like a lot more steps right there so exercise to right here try this out on your own

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Math 7 - Module 2B - Lesson 13 Day 1

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