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Adding decimals with ones, tenths and hundredths

Sal adds numbers, such as 3.53+4.72, by breaking them down into place values.

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  • winston baby style avatar for user cwhitmore ( ∀ )ψ
    ☃ (UPVOTE PLZZZZZZZZ) IF this gets 30 upvotes I will type 500 ☃s
    (32 votes)
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  • leafers seedling style avatar for user David.M.Meyer
    how do you do the addition of decimals more simple?
    (15 votes)
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    • piceratops ultimate style avatar for user Hecretary Bird
      Adding up decimals is as easy as adding up whole numbers. If you line up the place values correctly, the addition is the same. Whenever you set up a decimal addition problem, just double-check that the tenths place of the first number lines up with the tenths place of the second number and so on.
      (7 votes)
  • male robot johnny style avatar for user 31icwest
    I never saw cwhitmore type 500 ☃️s
    (10 votes)
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  • male robot johnny style avatar for user 31icwest
    Upvote me if you never saw cwhitmore type 500 ☃️s
    (7 votes)
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  • blobby green style avatar for user ayaan.yousufi
    is 10 tenths 1 whole?
    (4 votes)
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  • duskpin sapling style avatar for user joe
    what do we do for the thousandths
    (4 votes)
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  • cacteye purple style avatar for user Rylan
    how do you do the addition of decimals more simple?
    (4 votes)
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    • leaf yellow style avatar for user SP
      Think of adding with decimals as adding with normal numbers. For example:
      8.74 + 9.3
      You can write 9.3 as 9.30, as I will do for this example:
      8.74 → 874 and 9.3 → 930
      Then, add 874 and 930, which comes out to 1,804.

      Finally, put the decimals back in. Your answer should come out to be 18.04. Check it with a calculator -- it's correct.
      (4 votes)
  • cacteye blue style avatar for user maggie.mccune
    3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067982148086513282306647093844609550582231725359408128481117450284102701938521105559644622948954930381964428810975665933446128475648233786783165271201909145648566923460348610454326648213393607260249141273724587006606315588174881520920962829254091715364367892590360011330530548820466521384146951941511609433057270365759591953092186117381932611793105118548074462379962749567351885752724891227938183011949129833673362440656643086021394946395224737190702179860943702770539217176293176752384674818467669405132000568127145263560827785771342757789609173637178721468440901224953430146549585371050792279689258923542019956112129021960864034418159813629774771309960518707211349999998372978049951059731732816096318595024459455346908302642522308253344685035261931188171010003137838752886587533208381420617177669147303598253490428755468731159562863882353787593751957781857780532171226806613001927876611195909216420198938095257201065485863278865936153381827968230301952035301852968995773622599413891249721775283479131515574857242454150695950829533116861727855889075098381754637464939319255060400927701671139009848824012858361603563707660104710181942955596198946767837449448255379774726847104047534646208046684259069491293313677028989152104752162056966024058038150193511253382430035587640247496473263914199272604269922796782354781636009341721641219924586315030286182974555706749838505494588586926995690927210797509302955321165344987202755960236480665499119881834797753566369807426542527862551818417574672890977772793800081647060016145249192173217214772350141441973568548161361157352552133475741849468438523323907394143334547762416862518983569485562099219222184272550254256887671790494601653466804988627232791786085784383827967976681454100953883786360950680064225125205117392984896084128488626945604241965285022210661186306744278622039194945047123713786960956364371917287467764657573962413890865832645995813390478027590099465764078951269468398352595709825822620522489407726719478268482601476990902640136394437455305068203496252451749399651431429809190659250937221696461515709858387410597885959772975498930161753928468138268683868942774155991855925245953959431049972524680845987273644695848653836736222626099124608051243884390451244136549762780797715691435997700129616089441694868555848406353422072225828488648158456028506016842739452267467678895252138522549954666727823986456596116354886230577456498035593634568174324112515076069479451096596094025228879710893145669136867228748940560101503308617928680920874760917824938589009714909675985261365549781893129784821682998948722658804857564014270477555132379641451523746234364542858444795265867821051141354735739523113427166102135969536231442952484937187110145765403590279934403742007310578539062198387447808478489683321445713868751943506430218453191048481005370614680674919278191197939952061419663428754440643745123718192179998391015919561814675142691239748940907186494231961567945208095146550225231603881930142093762137855956638937787083039069792077346722182562599661501421503068038447734549202605414665925201497442850732518666002132434088190710486331734649651453905796268561005508106658796998163574736384052571459102897064140110971206280439039759515677157700420337869936007230558763176359421873125147120532928191826186125867321579198414848829164470609575270695722091756711672291098169091528017350671274858322287183520935396572512108357915136988209144421006751033467110314126711136990865851639831501970165151168517143765761835155650884909989859982387345528331635507647918535893226185489632132933089857064204675259070915481416549859461637180270981994309924488957571282890592323326097299712084433573265489382391193259746366730583604142813883032038249037589852437441702913276561809377344403070746921120191302033038019762110110044929321516084244485963766983895228684783123552658213144957685726243344189303968642624341077322697802807318915441101044682325271620105265227211166039666557309254711055785376346682065310989652691862056476931257058635662018558100729360659876486117910453348850346113657686753249441668039626579787718556084552965412665408530614344431858676975145661406800700237877659134401712749470420562230538994561314071127000407854733269939081454664645880797270826683063432858785698305235808933065757406795457163775254202114955761581400250126228594130216471550979259230990796547376125517656751357517829666454779174501129961489030463994713296210734043751895735961458901938971311179042978285647503203198691514028708085990480109412147221317947647772622414254854540332157185306142288137585043063321751829798662237172159160771669254748738986654949450114654062843366393790039769265672146385306736096571209180763832716641627488880078692560290228472104031721186082041900042296617119637792133757511495950156604963186294726547364252308177036751590673502350728354056704038674351362222477158915049530984448933309634087807693259939780541934144737744184263129860809988868741326047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
    (5 votes)
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  • starky tree style avatar for user Uncle Dingus Garfunkel linkle dunkel
    how do you add 4079.59666 and 56464644.4982
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  • piceratops seedling style avatar for user SankeerthramaM
    River dolphins are a polyphyletic group of fully aquatic mammals that reside exclusively in freshwater or brackish water. They are an informal grouping of dolphins, which itself is a paraphyletic group within the infraorder Cetacea. Extant river dolphins are placed in two superfamilies, Platanistoidea and Inioidea. They comprise the families Platanistidae (the South Asian dolphins), the recently extinct Lipotidae (Yangtze river dolphin), Iniidae (the Amazonian dolphins) and Pontoporiidae. There are five extant species of river dolphins. River dolphins, alongside other cetaceans, belong to the clade Artiodactyla, with even-toed ungulates, and their closest living relatives the hippopotamuses, from which they diverged about 40 million years ago. Specific types of Dolphins can be pink.[1]

    River dolphins are relatively small compared to other dolphins, having evolved to survive in warm, shallow water and strong river currents. They range in size from the 5-foot (1.5 m) long South Asian river dolphin to the 8-foot (2.4 m) and 220-pound (100 kg) Amazon river dolphin. Several species exhibit sexual dimorphism, in that the males are larger than the females. They have streamlined bodies and two limbs that are modified into flippers. River dolphins use their conical-shaped teeth and long beaks to capture fast-moving prey in murky water. They have well-developed hearing that is adapted for both air and water; they do not really rely on vision since the water they swim in is usually very muddy. Instead, they tend to rely on echolocation when hunting and navigating. These species are well-adapted to living in warm, shallow waters, and, unlike other cetaceans, have little to no blubber.

    River dolphins are not very widely distributed; they are all restricted to certain rivers or deltas. This makes them extremely vulnerable to habitat destruction. River dolphins feed primarily on fish. Male river dolphins typically mate with multiple females every year, but females only mate every two to three years. Calves are typically born in the spring and summer months and females bear all the responsibility for raising them. River dolphins produce a variety of vocalizations, usually in the form of clicks and whistles.

    River dolphins are rarely kept in captivity; breeding success has been poor and the animals often die within a few months of capture. As of 2015, there were only four river dolphins in captivity.
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Video transcript

- Let's do some more involved examples using decimals. So, let's say we wanna add four and 22 hundredths to 61 and 37 hundredths. Like always, I encourage you to pause the video and try to figure out on your own. Well the way that my brain tries to tackle it, is it says, alright, I have four and 22 hundredths, and 61 and 37 hundredths, how about I add the four plus the 61, so it's gonna be four plus 61, and then separately let me add the 22 hundredths to the 37 hundredths, so then I'm gonna add 22 hundredths plus 37 hundredths, and so four plus 61 is going to be equal to 65, and then 22 hundredths plus 37 hundredths, well, what's 22 plus 37? Let's see, 20 plus 30 is 50, and then two plus seven is nine, and so it's going to be 59 hundredths. So 59 hundredths, so it's gonna be 65 and 59 hundredths, which we can write as 65 and 59 hundredths. Now like I've mentioned in previous videos, there's many different ways of adding decimals, and in future videos we'll learn arguably faster ways of doing it, but I wanna show you multiple ways so you get a sense of ways to approach it, and this is the way that I do it in my head if someone said hey, something cost $61.37, and then you had to pay $4.22 in tax, how much did you have to pay in total, this is how I would actually do it in my head, I would get $65.59. Let's do another example. So let's say that we have three and 53 hundredths, and we wanna add that to four and 72 hundredths, like always, pause this video and see if you can figure it out on your own. So like we did in the previous example, we can say alright, we could add the ones, three ones plus four ones, so it's gonna be three plus four, and then we could add the hundredths, and we could say plus 53 hundredths, plus 53 hundredths, plus 72 hundredths, plus 72 hundredths, now the three plus four is pretty straightforward, that's just going to be ... Yup, blue color, this is just going to be equal to seven, but what is 53 hundredths plus 72 hundredths? Well, what's 53 plus 72? I'm going to write it this way, this is 53 hundredths, hundredths, and this is 72 hundredths, well, three plus two is going to be equal to five, and then 50 plus 70 is equal to 120, so this is going to be 125 hundredths, 125 hundredths, so how we write 125 hundredths as a decimal or just as a number? Well, there's a couple of ways to think about it, you could view this as 100 hundredths, hundredths, plus 25 hundredths, plus 25 hundredths, and the reason why I picked 100 hundredths, is because 100 hundredths make a whole, plus 25 hundredths, and so 100 hundredths is just going to be one, so this is going to be one plus 25 hundredths, so I could write this one plus 0.25, and remember, I'm adding that to the seven here, so it's gonna be seven, plus the one, plus the 25 hundredths, so when we added the 53 hundredths plus the 72 hundredths, we got 125 hundredths, which is the same thing as one and 25 hundredths, now, the one, we could add in the ones to the other ones, and so this is going to be seven plus one, is equal to eight, eight and 25 hundredths, so 8.25. Now, I'm going to introduce you a little bit to how people might tackle this more systematically, and I want you to think about how this is the exact same thing that we just did. So what you're going to see in the future is people are gonna say oh you line up the decimals, so 3.53 plus 4.72, and the reason why people say line up the decimals is so that you're adding the right places to the right places, 4.72, and then they say alright, we'll just go place by place and add it up, which is essentially what we just did without doing it as organized of a way here, and I did it this way so that you really get the understanding of what's going on. But you could say alright, I have three hundredths plus two hundredths, so I'm adding in the hundredths place, so three hundredths plus two hundredths is five hundredths, and then you could say okay, then I have 50 hundredths plus 70 hundredths, which I did over here, or you could view this as five tenths plus seven tenths, and five tenths and seven tenths is going to be equal to 12 tenths, but you can't write 12 tenths in the tenths place, but what you can do, so five plus seven is going to be 12 tenths, but 12 tenths is the same thing as one and two tenths, so you can write the two tenths in the tenths place, and then you take the one and you put it in the ones place, so five tenths plus seven tenths is one and two tenths, and then you add the ones up, and so you get one plus three plus four is eight, so it's eight and two tenths and five hundredths, or eight and 25 hundredths, or 8.25, the exact same thing any way that you try to tackle it, but hopefully it makes sense what's actually going on, you're adding hundredths to hundredths, tenths to tenths, ones to ones, and when, say you add tenths to tenths, and you get something that's larger than one, well, that part that is a whole number, you can put in the ones place, and we'll get much much more practice with this in future videos.