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6th grade
Course: 6th grade > Unit 2
Lesson 1: Adding decimalsAdding decimals: 0.822+5.65
Adding decimals is a breeze when you follow these simple steps: First, line up the decimal points and write the numbers one below the other. Next, start adding from the smallest place value (thousandths) and carry over any extra value to the next place if needed. Finally, include the decimal point in your answer. Mastering decimal addition helps build strong math skills for everyday life.
. Created by Sal Khan.
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- Why do you put the smallest decimal on top and the longest decimal on the bottom?(15 votes)
- It doesn't matter which decimal value is longer or shorter to write, or which comes first or second…
In the video Sal arranged the higher valued decimal on top, (he placed the value with 5-whole over the 0-whole), and says it is just his preference, and it would add the same either way.0:10
because…
★ Addition is Commutative, (able to be rearranged and still add the same).
2 + 5 = 7
5 + 2 = 7
★We can have either decimal value on top or bottom, but…
★ We must LINE UP THE DECIMALS to keep each place value aligned throughout the calculation.
0.822 + 5.65 = ?0.822
+ 5.65
————————
6.472 ←same answer
5.65
+ 0.822
————————
6.472 ←same answer
★Use the decimals to guide the place value alignment: line up the decimals above and below, then add each column of numbers, empty spaces are equal to zero.
(ㆁωㆁ) Hope this helps someone!(18 votes)
- Hey, what if you had 9.78 - 3.2? What would I do with the 8?(12 votes)
- You would do 9.78-3.20 which would be 6.58(7 votes)
- hi
can you divide the ten by the two hundred(8 votes)- yes bc it will turn out to be 2000 thing for asking(6 votes)
- in the equation, do you put 0.822 on the top or 5.65? its confusing...(9 votes)
- 5.65 on top and then you put a 0 after the 5 and then you put the 0.822 and add(5 votes)
- When exactly the "standard algorithm" happens in this solution?(5 votes)
- To use the standard algorithm, follow these steps in order:
Line up the decimal points36.413
12.5
+ 30.08
------------
Fill in the blank spots with zeros36.413
12.500
+ 30.080
------------
Add, beginning with the smallest place first
thousandths: 3+0+0=3
hundredths: 1+0+8=9
tenths: 4+5+0=9
ones: 6+2+0=8
tens: 3+1+3=7
Be sure to drop the decimal down into the answer36.413
12.500
+ 30.080
------------
78.993
Hope this helps!(5 votes)
- Can you always do that stragegy(4 votes)
- upvote this to get squishmallows and 1000,0000,0000,000,000,000,000,0000,robux(7 votes)
- When i was in 5th grade my teacher always said to say "and" instead of "point". So which one is right?(2 votes)
- My teacher said it was "and".That is what my teacher told me.(4 votes)
- are there questions on these or not?(1 vote)
- Most of these newer comments are really weird(6 votes)
- Can anyone help me? I did not get it. Please? Thanks for your participation!🙂(4 votes)
- I wish I can help but I am having trouble on it too. And how did you get the emoji?(0 votes)
Video transcript
We're asked to
add 0.822 to 5.65. So let me rewrite this. And when I rewrite it, I
want to line up the decimals so that we add the right
place to the right place. And so we could write
either number first, although I like to write
the larger number first. So let's write 5.65. And remember, the
important thing is that we line up
the decimal points. So if we write 0.822-- so
we line up the decimal. Let me line up
the decimal first. So I'll write the decimal
right below the other decimal. And it is 0.822. And now we are ready to add. So let's see what's
going on here. So I like to start in
the smallest place. That way, the carrying
works out well. So you might say, wait,
I need to add this 2 thousandths to something. I don't see anything up here. Well, you could say there's just
a 0 thousandths right up here. Then it makes it very clear. Well, 0 thousandths
plus 2 thousandths is going to be 2 thousandths. 5 hundredths plus 2
hundredths is 7 hundredths. 6 tenths plus 8
tenths is 14 tenths. Well, 14 tenths is the same
thing as 4 tenths and 1 one. Another way of thinking about
it is you're carrying the 1. But really, what you're saying
is, look, this is 14 tenths. I could write it as 4 tenths
and a 1, or a ones place, a 1 in a ones place. Then you have 1 plus 5 is 6. And of course, you cannot
forget the decimal. The decimal goes right there. And this is 6.472.