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## 5th grade

### Course: 5th grade > Unit 9

Lesson 2: Divide whole numbers to get a decimal quotient# Divide whole numbers with decimal quotients: 5÷2

CCSS.Math:

Sal uses fractions and place value strategies to divide simple whole numbers like 5÷2 to get decimal quotients. Created by Sal Khan.

## Want to join the conversation?

- why is doing this hard(18 votes)
- I dont know.All I know is i'm on your side.It's hard.(16 votes)

- Why does it make sense to equate 5/2 as 50 tenths / 2 = 25 tenths = 2.5

But, 12 / .5 = 120 tenths / 5 tenths = 24 and not 24 tenths, which would be 2.4.

How do you decide which equations to drop the extra tenths.

Following the rule of converting to tenths, wouldn't it make sense to say:

50 tenths / 20 tenths =(16 votes)- Tbh I don't know either...(7 votes)

- So 5 ÷ 2 = 5/2 (0:47) , which as a improper fraction is 2 1/2 (1:10). 2 1/2 as a decimal is 2.5 (1:25), so 5 ÷ 2 is equal to 2.5, right? Please tell me if I made any mistakes, I'd like to know.
*Thx!*(8 votes)- You did not make any mistakes in your calculations, but remember that improper fractions are fractions with a numerator greater than the denominator; 5/2 is already an improper fraction.

Values with both a whole number and a proper fraction combined are mixed fractions, so the 2 (and) 1/2 is a mixed fraction.(10 votes)

- How am i supposed to do this!(8 votes)
- If you divide 5/2, think about 1/2 of a pizza. If you have 5 of the 1/2 pizzas, you can put two sets of two 1/2 pizzas to make 2 full pizzas, and you still have 1/2 a pizza left, so you have a total of 2 1/2 pizzas. 5/3 would be 1 full pizza and 2/3 left, so 1 2/3.(6 votes)

- do you like these things⌚️📱💻⌨️🖥️🖱️🎮🍣.(9 votes)
- Yes I do very much(0 votes)

- How does this make sense like how do you turn a whole number into a fraction then into a decimal! Whats next how to turn 1+1 into a book?(9 votes)
- I think that people just get a little too into the grove and start using hard examples to demonstrate how to do this or/and some people just have a hard time understanding things a different way then they are used to and freak out about it. I understand that this is tricky it is for me too but we HAVE to learn this if not ..... bad things could happen. So, please follow this piece of advice: No matter what try your best; ask questions and always wonder. If you do things will feel much better. And every day in the morning or when you have time meditate and think that your life is a video and you have many fans so you will always have a positive and good spirit.(1 vote)

- Tbh the video doesn’t really help me with the questions I’m getting, I can easily do five divided by two, but questions I’m getting are seven divided by twenty, which this video doesn’t help answer.(8 votes)
- this is the easy way.20*5=100,7*5=35.35/100=0.35(3 votes)

- So 5 ÷ 2 = 5/2 (0:47) , which as a improper fraction is 2 1/2 (1:10). 2 1/2 as a decimal is 2.5 (1:25), so 5 ÷ 2 is equal to 2.5, right? Please tell me if I made any mistakes, I'd like to know.(7 votes)
- Why does it make sense to equate 5/2 as 50 tenths / 2 = 25 tenths = 2.5

But, 12 / .5 = 120 tenths / 5 tenths = 24 and not 24 tenths, which would be 2.4.

How do you decide which equations to drop the extra tenths.

Following the rule of converting to tenths, wouldn't it make sense to say:

50 tenths / 20 tenths =(6 votes) - Can u please make a video about this by using different numbers to divide? In the exercise it says 3 ÷ 4 = ? which is confusing because it doesn't say how to do those kinds of questions. Thank you!:)(5 votes)
- do it like this,4 can't go into 3 so we add a decimal.30/4=7 and a remainder of 2 so we add another decimal.20/4=5.you get 0.75(2 votes)

## Video transcript

- [Instructor] So in this video, we're going to think
about dividing numbers where the quotient, the
result of our division, might result in a decimal. So let's say we wanted to compute what five divided by two is. In the past, you might've said, hey, two times two is four and then you'd have one leftover and so you might have
said something like this, this is two with a remainder of one. But now we don't want,
we don't wanna just say, hey, how many times can it
go in and what's left over. We wanna know exactly how many
times can two go into five so we want a decimal
answer right over here. So, pause this video and see
if you can figure that out. All right, now let's work
through this together. And there's many ways that
we could approach this. One way is to realize
that five divided by two, we could re-express as five divided by two or as five halves and five
halves is the same thing as four plus one over two which is the same thing as
four halves plus one half which is the same thing
as four halves is two. Let me do that in a different color. This part over here is two and then you have this one half. So it's the same thing as two and a half and if we were to
express that as a decimal that's going to be equal to two and how many tenths is equal to a half? Well five tenths is equal to a half. So five divided by two,
you could say, 2.5. Now another way that you could
approach this is you say, five divided by two is the same thing as 50 tenths divided by two. So let me use a different color here. So instead of a five, I could say five is the same thing as 50 tenths, 50 tenths divided by, divided by two and so if I have 50 of something and if I were to divide it by two, well that's going to result
in 25 of the something. So this is going to be equal to 25 tenths. And how would we express
25 tenths as a decimal? Well, this is going to be equal to, if I could put some place values here, so we definitely have five tenths. I'll put that in the tenths place and then 20 tenths is the
same thing as two ones. And that's exactly what we had up here. Either way, you get 2.5, two ones and five tenths.