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### Course: Algebra basics > Unit 1

Lesson 8: Operations with decimals- Adding decimals: 9.087+15.31
- Adding decimals: 0.822+5.65
- Adding decimals: thousandths
- Subtracting decimals: 9.57-8.09
- Subtracting decimals: 39.1 - 0.794
- Subtracting decimals: thousandths
- Multiplying decimals example
- Multiplying challenging decimals
- Decimal multiplication place value
- Dividing decimals with hundredths
- Dividing by a multi-digit decimal
- Dividing decimals: hundredths

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# Subtracting decimals: 9.57-8.09

Learn to subtract decimals by aligning the decimal points and place values. Regroup numbers for easier subtraction, and then perform the subtraction for each place value. Mastering decimal subtraction helps build strong math skills and real-world problem-solving abilities. Created by Sal Khan.

## Want to join the conversation?

- As I do these exercises and get further into Khan Academy, I keep wondering if people can do these exercises easily in their head. Give me a pen and paper and these problems are like nothing, because I understand them conceptually, but in my head I can barely keep track of the answers generated at each step.

Just curious if I'm the only one that needs a pen and paper for this simple stuff.(19 votes)- Some people can do these kinds of things in their heads, but don’t beat yourself up if you can’t. It gets easier with practice and as you find your own shortcuts. :)(13 votes)

- To anyone who reads this, always remember:

YOU ARE smart

YOU ARE important

YOU ARE strong

YOU ARE enough

anyone who likes this please vote

have a good day❤(21 votes)- Thank u so much, u are very kind, do u have any friends? If not, would like to be my friend?(1 vote)

- Thanks vid you helped me please people put the arrow up I don't know why but just do it I have 47000 points(8 votes)
- I don't understand this concept on the video(2 votes)
- Try to do the problems without the decimals first and then try to put them back and do them.

It should still all work the same way. The only difference is that the numbers that are to the right of the decimal are just showing that they are units but they are not enough to create 1 whole unit.(5 votes)

- i know that you are a real person so do not act like a computer(1 vote)
- He isn't acting like a computer! His brain is a computer though! :D(5 votes)

- How are people remembering all of this when I barely remember it and how do people do this in there head and decimals confuse me like for example 0.389 I think its zero point three hundred eighty nine but its not. Its so hard and I'm in fifth grade(3 votes)
- Different people have different abilities. For instance, I have ADHD and I can only keep a limited number of things in my mind at once (SQUIRREL!). So, I also have a hard time doing
*any*math in my head unless I'm taking my medication.

I also have a hard time doing complicated math if I'm not familiar with it. The best thing to do, if you have a hard time doing it in your head, is to**not**do that. Use paper (or a tablet with a stylus) to do the math. I'm well past 5th grade, but I still have to sometimes use my tablet to do the math.

Don't try to compete against other people, you won't do yourself any favors. Learn to do the math correctly in the manner in which you can most easily do it.

There's nothing wrong with being unable to do the math in your head, and it won't stop you from succeeding. I do quite well even though I can't do math in my head. So can you.(1 vote)

- I now how to do it but I can't do it sideways I now it doesn't mater if it is sideways or not(2 votes)
- its kinda the same but i really like this unit so ill get it dowm(1 vote)

- i dont get this it dosent give me move edvice(2 votes)
- What do you not get? Maybe if you have a different math resource, maybe you should go to that. I don't get all my questions answered on khan academy either.(2 votes)

- What is "standard algorithm"?(1 vote)
- It is the standard or original way to do the math, like dividing or multiplying.(3 votes)

- if I go on youtube and search this will this vid come up? Or is it only on the site?(1 vote)
- did you know that this is on the site and on youtube too(2 votes)

## Video transcript

Let's try to subtract
9.57 minus 8.09. So try to pause this video
and figure this out first before we work
through it together. All right. Well, let's just rewrite it. Let's rewrite it. And when I rewrite it, I
like to line up the decimals. This one it's a
little intuitive. We have 8.09. Just like that, and now
we're ready to subtract. And we want to subtract 9
hundredths from 7 hundredths. Well, we don't have
enough hundredths up here so let's move over here. Let's see if we can do some
regrouping so we always have a higher number on top. So over here we want to
subtract 0 tenths from 5 tenths so we have enough
tenths over here. So let's regroup. So instead of 5 tenths,
I'm going to have 4 tenths, and then I'm going to give
that other tenth, which is the same thing as 10
hundredths over here, so this becomes 17 hundredths. 17 minus 9 is 8. 4 minus 0 is 4. And then I have 9 minus 8 is 1. So this is going to be 1.48.