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?(16 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
★ 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 = ?
6.472 ←same answer
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)
can you divide the ten by the two hundred(8 votes)
- in the equation, do you put 0.822 on the top or 5.65? its confusing...(9 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 points
Fill in the blank spots with zeros
Add, beginning with the smallest place first
Be sure to drop the decimal down into the answer
Hope this helps!(5 votes)
- are there questions on these or not?(1 vote)
- Can anyone help me? I did not get it. Please? Thanks for your participation!🙂(4 votes)
- why do the assignments have due dates(1 vote)
- Your assignments have due dates because your teacher or parent assigned them to you, so I recommend completing them before or by that date.(1 vote)
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.