I just realized, decimals and whole numbers are very different. If you put a 0 in a decimal, it makes no difference, but in a whole number, it makes so much difference.

True. 0.0 is just that--0. The same goes for 1.0, 2.0 3.0...they're just 1, 2, 3...; but without the decimal point they're 10, 20, 30...; 00 is still 0 though. Sorry 0!

hello, math is very frustrating for me and I usually end up depressed afterwards. Does anybody have tips to help me stay happy about math?

First, make sure you have memorized your basic math facts. That's all of the addition/subtraction and multiplication/division facts up to 10+10 and 10x10. Next, figure out which things you are not understanding as well as you'd like and practice them. For example, I found your question in the "6th Grade" section so I assume something about 6th grade math is causing problems. Did you find 5th grade math OK? If not, use Khan Academy to review and relearn 5th grade math. If you find things in that section that are confusing, try the 4th grade section. As you review and relearn previous years math, you'll find the current year getting easier. Will it take time? Yes. But it will be worth it. As ellajahcat says, Math is important for life. No matter what type of job you end up in, you'll need math.

do you always have to line up the decimais

It's less prone to mistakes, as long as the decimal places are added to the correct decimal place it's alright, but when they aren't lined up the chances of making a mistake increases.

Main content

Grade 6 (Virginia)

Course: Grade 6 (Virginia) > Unit 4

Lesson 1: Adding & subtracting decimals

Adding decimals word problem

Name: Adding decimals word problem
Uploaded: 2013-07-25T18:52:12Z
Description: Adding decimals is an essential math skill. In this example, we find the total weight of newborn twins. Nadia weighs 7.27 pounds, and Vanessa weighs 8.34 pounds. By carefully lining up the decimals and adding the numbers, we discover their combined weight is 15.61 pounds.

CCSS.Math:

6.NS.B.3

Google Classroom

Adding decimals is an essential math skill. In this example, we find the total weight of newborn twins. Nadia weighs 7.27 pounds, and Vanessa weighs 8.34 pounds. By carefully lining up the decimals and adding the numbers, we discover their combined weight is 15.61 pounds. Created by Sal Khan.

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POTATO :)
Posted 5 years ago. Direct link to POTATO :)'s post “I just realized, decimals...”
I just realized, decimals and whole numbers are very different. If you put a 0 in a decimal, it makes no difference, but in a whole number, it makes so much difference.
Button navigates to signup pageComment on POTATO :)'s post “I just realized, decimals...”
(13 votes)
Answer
- quack123
  Posted 2 years ago. Direct link to quack123's post “True. 0.0 is just that--0...”
  True. 0.0 is just that--0. The same goes for 1.0, 2.0 3.0...they're just 1, 2, 3...; but without the decimal point they're 10, 20, 30...; 00 is still 0 though. Sorry 0!
  Comment on quack123's post “True. 0.0 is just that--0...”
  (7 votes)
Jamyla Smith
Posted 7 years ago. Direct link to Jamyla Smith's post “more hints because some p...”
more hints because some people dont understand it well from the understanding of the hints
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(11 votes)
Answer
- rashmi101083
  Posted 3 years ago. Direct link to rashmi101083's post “* I agree with you someti...”
  * I agree with you sometimes it happens with me also and I think that it happens with everyone if true then like and tell
  Give reply*
  Comment on rashmi101083's post “* I agree with you someti...”
  (0 votes)
SBEAST
Posted 2 months ago. Direct link to SBEAST's post “⠀⠀⠀⢀⣀⣀⡀⠀⠀⠀⠀⠀⠀⠀⣀⣤⣴⠶⠿⠛⠛⠛⠛⠛⠛...”
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⠀⠀⠀⠉⠛⠛⠿⠿⠶⠶⠶⠶⠶⠿⠿⠿⠟⠛⠛⠋⠉⠀⠀⠀⠀⠀⠉⠉⠛⠛⠻⠿⠿⠿⠶⠶⠶⠶⠶⠾⠿⠛⠛⠋⠁⠀⠀This should be top voted
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(9 votes)
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Kelly
Posted 9 years ago. Direct link to Kelly's post “do you always have to lin...”
do you always have to line up the decimais
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(1 vote)
Answer
- Barrett Southworth
  Posted 9 years ago. Direct link to Barrett Southworth's post “It's less prone to mistak...”
  It's less prone to mistakes, as long as the decimal places are added to the correct decimal place it's alright, but when they aren't lined up the chances of making a mistake increases.
  Comment on Barrett Southworth's post “It's less prone to mistak...”
  (16 votes)
kvaughn
Posted 8 years ago. Direct link to kvaughn's post “i am still having a hard ...”
i am still having a hard time because it dose not make sense to me at all so please tell me the meaning of this please make an different video cuz i having hard time.
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(6 votes)
Answer
Ann Vu
Posted 5 months ago. Direct link to Ann Vu's post “Thanks sal!😀”
Thanks sal!😀
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(6 votes)
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ellajahcat
Posted 7 years ago. Direct link to ellajahcat's post “hello, math is very frust...”
hello, math is very frustrating for me and I usually end up depressed afterwards. Does anybody have tips to help me stay happy about math?
Button navigates to signup pageComment on ellajahcat's post “hello, math is very frust...”
(4 votes)
Answer
- KathyC
  Posted 7 years ago. Direct link to KathyC's post “First, make sure you have...”
  First, make sure you have memorized your basic math facts. That's all of the addition/subtraction and multiplication/division facts up to 10+10 and 10x10.
  Next, figure out which things you are not understanding as well as you'd like and practice them. For example, I found your question in the "6th Grade" section so I assume something about 6th grade math is causing problems. Did you find 5th grade math OK? If not, use Khan Academy to review and relearn 5th grade math. If you find things in that section that are confusing, try the 4th grade section. As you review and relearn previous years math, you'll find the current year getting easier.
  Will it take time? Yes. But it will be worth it. As ellajahcat says, Math is important for life. No matter what type of job you end up in, you'll need math.
  Button navigates to signup page
  (3 votes)
FlamingHotdog
Posted a month ago. Direct link to FlamingHotdog's post “can you guys make it so w...”
can you guys make it so when you get a problem wrong, you can redo it and get the point?
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jamie breedlove
Posted a year ago. Direct link to jamie breedlove's post “im back from the dead”
im back from the dead
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- 52246
  Posted 2 months ago. Direct link to 52246's post “yo yo yo”
  yo yo yo
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morganh
Posted a month ago. Direct link to morganh's post “I just don't like khan ac...”
I just don't like khan academy
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(4 votes)
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- 29ryweaver
  Posted a month ago. Direct link to 29ryweaver's post “same”
  same
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  (2 votes)

Video transcript

On Saturday, William's parents gave birth to twins and named them Nadia and Vanessa. When they were first born, Nadia weighed 7.27 pounds and was 21.5 inches tall, and Vanessa weighed 8.34 pounds. How much did the babies weigh in total? So they tell us Nadia weighed 7.27 and Vanessa weighed 8.34. We have to add those up. And really, they just gave us this. The length of Nadia at birth really is a distraction, just so that we just don't mindlessly add any numbers we see. So this is really unnecessary information just to distract us. So we need to add Nadia's birth weight plus Vanessa's. So it's 7.27. So 7.27 plus 8.34. And it's always important that we line up the decimal. And I'd like to do the decimal first. So it's 8.34. And we'll just add these two up. So 7 plus 4, and this is really 7/100 plus 4/100 is 11/100, which is the same thing as 1/100 and 1/10. 1/10 plus 2/10 plus 3/10 is 6/10. We've got our decimal sign right over there. And then 7 plus 8 is 15, or you could even say it's five 1's and one 10. And we're done. They weighed 15.61 pounds in total.