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## 5th grade

### Course: 5th grade > Unit 9

Lesson 3: Divide decimals by whole numbers# Dividing a decimal by a whole number with fraction models

The video explores the concept of dividing decimals by whole numbers. It emphasizes visualizing the process, using the idea of converting tenths to hundredths to make division more intuitive.

## Want to join the conversation?

- can i get the most votes pls(25 votes)
- yeah no you cant(0 votes)

- i needed to explain to my sister that 0.4 s the same as 0.40 and then she was like, "But 40 is bigger than 4!"

That's 30 minutes I will never get back again.(12 votes)- you just say add a 0 your welcome.(0 votes)

- Would we be able to do it this way?

0.4= 4/10

5=5/1

and then divide normaly?(5 votes)- Yes, you can.

(4 / 10) / (5 / 1) = (4 / 10) * (1 / 5) = (4 / 50) = 0.08(3 votes)

- Does anyone else find this a little confusing? Because how do you know that the "8" is supposed to be in the hundreths??(4 votes)
- so 8 times 5 = 40 and in this instance the

the 4 in the forty is in the tens place

the 0 is in the ones place.

The 8 and 5 are in the ones place.

sooooo

0.40 is like 40 all over again.

The 4 is in the tenths place

The zero is in the hundreths place

S0 the 8 and the 5 are in the hundreths place.(2 votes)

- Why can’t you do it this way?

0.4*10 = 4

5*10 = 50

4/50 = 1/(50/4)

1/(50/4) = 1/12.5

1/12.5 = 8/100

8/100 = 0.08(4 votes) - So if you remember your place values, number beyond the one place is consider 1/10 of that value or is being divided by 10

so when Khan made 0.4(4/10) into 0.40(40/100), he made equivalent fractions that hold the same value(enter into a calculator if you don't see it)

40 / 5 = 8

and just like 400 / 5 = 80

4/5 = 0.8

and

.4 / 5 = 0.08(6 votes)

- What would happen if you converted the decimal to a fraction and divided that by a whole number instead of dividing a decimal by a whole number and converted your final answer to a decimal? Would the answer be different from the original answer you would have gotten if you had divided the decimal by the whole number as a decimal? If you get what I mean, COMMENT:
*CHB***winkwink pjo hoo toa**. Please leave an answer to this problem using both ways(3 votes)- The answer will be different. Let’s say 0.2 is 1/5 then you divided it by 8/1. You get 0.025 which is different than 0.2.(1 vote)

- upvote if you have seen kong skull island(2 votes)
- Why is the final answer in that video 0.08? It doesn't make any sense to me...(1 vote)
- 40÷5 equals 8. Because we are talking about hundredths, it's 0.08(1 vote)

## 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.