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## Divide decimals by whole numbers

Current time:0:00Total duration:2:56

# Dividing a decimal by a whole number example

CCSS.Math:

## Video transcript

- [Instructor] Let's see if we can compute what 1.86 divided by two is. And like always pause this
video and have a go at it. And I'll give you a hint,
see if you can think about 1.86 as a certain
number of hundredths, and then divide that by two. All right now let's work
through it together. So as promised, let's see if we can think of 1.86 as a certain
number of hundredths. So if we go to the hundredths place, we only see six there, but we could view 8/10 as 80 hundredths. So you could view the
.86 as 86 hundredths, and each one is 100
hundredths, so we really have 186 hundredths. So this number right over here I'm going to rewrite as 186 hundredths, hundredths. And that is what we need to divide by two. Now, if you're dividing
186 of something by two, well it's just gonna be 186 divided by two of that something. So we could rewrite this
as 186 divided by two, and then that's the number of hundredths this is going to be, so I'll
put that in parenthesis. So it's going to be that
many hundredths, hundredths. All right, so what is 186 divided by two? Some of you might be able
to do it in your head, some of you might wanna use some paper. The way I like to think
about it is if I were to take the six ones and divide it by two, well that's going to be three ones. And then if I were to take the 18 tens and divided by two, that's
going to be nine tens, so that gets us to 93. Now you could've also
thought about it like this, you could've said, how many times does two go into 186? Let's see, it doesn't go into one, how many times does it go into 18? Nine times, nine times two is 18, we could subtract, and then you have zero, you bring down that six. Two goes into six three
times, three times two is six. You subtract and you get no remainders. So either way you're going to get 93. And it's 93 what? Well it's 93 hundredths, is
what we're talking about. 93 hundredths. And now we just wanna
express 93 hundredths as a decimal. Well how do we do that? Well that's gonna be 0 point. The 90 hundredths is
the same thing as 9/10, and then the three hundredths,
is of course 300 hundredths. Three in the hundredths place. So it's 0.93, and so we
can write it up here. This is going to be equal to 0.93, and we're done!