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Adding decimals is an essential math skill. To add decimals, such as 9.087 and 15.31, align the decimal points and place values. Fill in any missing digits with zeros to make the numbers the same length. Then, perform the addition as usual, starting with the smallest place value. The result of adding 9.087 and 15.31 is 24.397. Created by Sal Khan.

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• how did you get the decimals to line up with each other and why do you put a number off to the side
• You line up the decimal points.

Wrong
``  1.23 +45.6------- 0.579``

Correct
``  1.23+45.60-------- 46.83``
• how does this help us in a real life situation
• You have to use decimals when go shopping. because if something cost 28.34 and then you also get another thing that costs 15.24 you have to add them so u know how much u spending
• how do you do it
• 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

9.087 + 15.31 = ?
``   9.087+ 15.31—————————  24.397 ←🥳 answer``

★In Addition order doesn't matter, because it's Commutative, meaning we can rearrange addition and get the same answer,
1 + 7 = 8
7 + 1 = 8
So either decimal value can be first or second, but always line up the place values.
``  15.31+  9.087—————————  24.397 ←🥳 same answer``

★This method works for more than two values as well, as long as we always line up the decimals so that the place values form columns!

2.14 + 0.3421 + 3 + 11.2 = ?
``   2.14   0.3421   3+ 11.2——————————  16.6821 ←🥳 answer``

Rearranged,
with place keeper zeros…
``  11.2000   3.0000   0.3421+  2.1400——————————  16.6821 ←🥳 same answer``

★ Just remember: we must line up the decimals and keep the place values aligned throughout the calculation, move the decimal straight down, so it is aligned in the answer too, then it's just adding the columns like usual…

Start adding in the far right column, carry values to the left, etc…

(ㆁωㆁ) Hope this helps someone!
• is it allowed to add an zero at the whole number?
• I mean I get ur question. You can add a zero at a whole number. HOWEVER it won't change the answer. For example, 5+0=5. But it is allowed but no use.
• I made a chart and placed them into the chart to solve it, is that smart?
• yes, it is very smart! i learned how to solve it using a chart, and it's good that you still use it as a strategy! ^^
• his voice is nice :]
• Yes it is very
• Sal is a good teacher
• Is it compulsory to line the decimals
• Corresponding place values must be added together, the decimals naturally align when the columns are in the correct order.

Therefore aligning the decimals is an easy way to align the place values correctly into columns for manual addition.

So, when creating accurate addition columns, it is also compulsory to line up the decimals.
• The tip of adding decimals are that you should line up the decimal points together.
• Do you align the decimals even if you are multiplying decimals
• if you are multiplying decimals, you do not have to line up the decimal points. You keep the decimal points in the correct space in the numbers, but otherwise, write it out like a normal multiplication problem. You solve it like a normal problem too. so if it is 1.5 X 3.4, you would write it out like a normal multiplication problem:
2
3.4
x1.5
--------
1
1 7 0
+3 4 0
-------
5 1 0, but to put in the decimal point, you have to think of the original numbers, which were 1.5, and 3.4, 1.5 had one number to the right of the decimal point, so note that, and 3.4 also had one number to the right of the decimal point, So note that as well, add that up and it means that you have to put the decimal point in the problem so that it is to the left of two numbers, so the answer is not 510, it is 5.10.