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## Divide decimals by whole numbers

Current time:0:00Total duration:2:09

# Dividing a decimal by a whole number with fraction models

CCSS Math: 5.NBT.B.7

## Video transcript

- [Instructor] In this video, we're going to try to figure out what 4/10 divided by five is. So pause this video and see
if you can think about it before we work through it together. We're really going to think
about approaching this visually. All right, now let's work
through this together. Let's actually try to think
about what 4/10 looks like. So if you view this
entire square as a whole, you see that we've divided
it into 10 equal columns or 10 equal sections,
and four of those tenths are shaded in, so what you
see here in blue is 4/10. But how do we divide that into
five and make sense of it? Well, one way to think about it is to imagine 4/10 not just as 4/10, but to imagine it as 40/100, so this would be imagining it as 40/100. So we can re-write 4/10 divided by 5 as 40/100 divided by 5, and now we can think about
taking these 40 hundredths, each of these little
squares is a hundredth, and divide it into five equal sections, and then we can say,
well, how many hundredths are in each of those five equal sections? So let's do that. So let's see, this is one, this is two, this is three, this is four and then we have five equal sections. So how many hundredths are in
each of those equal sections? Well we can see in each of them you have one, two, three, four,
five, six, seven, eight. So 40/100 divided by five is going to be 8/100, because
we have eight of these little squares in each of
those five equal sections. So 8/100 we would like this. And so 40/100 divided by five is 8/100, then 4/10 divided by five
is also equal to 8/100.