Main content

## Arithmetic (all content)

### Unit 6: Lesson 7

Subtracting decimals- Subtracting decimals: 9.57-8.09
- Subtracting decimals: 10.1-3.93
- Subtracting decimals
- Subtract decimals < 1 (tenths)
- Subtracting decimals (tenths)
- Subtracting decimals and whole numbers (tenths)
- Subtract decimals < 1 (hundredths)
- Subtract decimals (hundredths)
- Subtract decimals and whole numbers (hundredths)

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# Subtracting decimals: 10.1-3.93

Sal subtracts 10.1-3.93 using "standard algorithm". Created by Sal Khan.

## Want to join the conversation?

- i feel so dumb sometimes i cant add and subtract in my head >.<(14 votes)
- It's okay, all you need is practice. Practice, pracTICE, PRACTICE(16 votes)

- It depends on how you like it to be. I like to go from right to left.(8 votes)
- What are minuend and subtrahend?(5 votes)
- Minuend is the number you "start with" in a subtraction.

Subtrahend is the number take from the minuend.

So in "3 - 2 = 1", 3 is the minuend and 2 is the subtrahend.(4 votes)

- I was taught to subtract from right to left, however he subtracts left to right..(4 votes)
- I was taught right to left to(1 vote)

- hi do you like sports(3 votes)
- do we always have to put the 0 in the equation?(3 votes)
- you do not have to. it is just a reminder(1 vote)

- uhhhhh wut why left to right ITS RIGHT TO LEFT BRO(3 votes)
- you need to line up the decimals.(1 vote)

- but what happens if you get an equation like this: 22-10.7?(0 votes)
- ok, so the first thing i would do is line it up.

22.0 I would add the zero on top of the seven

-10.7 21-10=11 and ten -7 is 3

So your answer is 11.3

Hope that helps(6 votes)

- 10.1-3.93 is so easy but a little bit hard(2 votes)
- Note that 3.93 is only 0.07 less than 4. So we can subtract 4 from 10.1 to get 6.1 (or 6.10), then add back 0.07 to get a final answer of
**6.17**.

Have a blessed, wonderful day!(2 votes)

- Whats 1+1x555555555(2 votes)

## Video transcript

Let's try to calculate
10.1 minus 3.93. And I encourage you
to pause this video and try it on your
own first, and then we can think about whether
we did it the same way. So let's just
rewrite it, aligning the decimal and the
different place values. So 10.1 minus-- the 3
is in the ones place, so I'll put it right
under the 0-- 3.93. Now, let's just try
to calculate this. Now, before we subtract, we
want all the numbers on top to be larger than the
numbers on the bottom. And we don't even
have a number here. We could stick a 0 here. Let me do that in a
different color here. We could stick a 0 here. 10.1 is the same thing as 10.10,
but we still face an issue here. 0 is less than 3. 1 is less than 9. 0 is less than 3. So we're going to do a
little bit of regrouping. So let's do that regrouping. So we could take a 10 away,
one 10 away, and then one 10 is the same thing as 10 ones. So I could write a
10 in the ones place. And I could take
one of those ones away so I'm going
to have nine ones, and give that one
to the tenths place. Well, one is 10 tenths. 10 tenths plus 1 tenth
is going to be 11 tenths. Now, I could take
one of those tenths away and give it to
the hundredths place. 1 tenth is 10 hundredths. And now I have a higher
digit in the numerator, or at least as equal
in the numerator as I have in the denominator. So 10 minus 3 is 7. 10 minus 9 is 1. I have the decimal. 9 minus 3 is 6. And then I have
nothing over here. So 10.1 minus 3.93, 6.17.