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### Course: 5th grade > Unit 9

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

This video teaches how to divide whole numbers to get a decimal quotient. It explains two methods to achieve this, emphasizing that division can result in decimals, not just whole numbers or remainders. Created by Sal Khan.

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- 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)- In the first equation, tenths appear only on top, so the tenths remain.

However, in the second equation, tenths appear on both top and bottom, so the tenths cancel out!(0 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!*(7 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 numbers, so the 2 (and) 1/2 is a mixed number.(10 votes)

- How am i supposed to do this!(5 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.(5 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)
- 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.(9 votes)
- 7/20 is easy you multiply both numbers by 5 you get 70/100 then put it into a decimal 70/100 = .70(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?(8 votes)
- Actually, turing 1+1 into a book would be easy. But, getting to the point, we can turn a whole number into a fraction by taking something away from it, and then put the number on the bottom on the right side of the decimal, and then putting the top number on the left. For example,

9

9-73/9=1/9

1/9=1.9

I hope this helped! Thx!(0 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 =(5 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!:)(4 votes)
- To do 3 divided by 4, we can divide 4 into 3, using long division.

4 goes into 3, zero times. Write 0 on top and a decimal point after the 0 (to line up with the decimal point after the 4).

4 goes into 30, seven times with 2 left over. Write the digit 7 on top, just after the decimal point.

4 goes into 20, five times exactly. Write the digit 5 on top, just after the 7.

So the answer (quotient) is 0.75.(0 votes)

- I don't understand how standard algorithm works,any help?(2 votes)
- Is there anything specific that I can help you with? Please let me know! :)(3 votes)

- Think about money.

1) If you have a $1 bill, you have a whole number amount.

2) You need change, so you convert your $1 bill into 4 quarters. Each quarter = 1/4 of $1. So, now you have 4 units of 1/4.

3) The value of one quarter is $0.25 (a decimal). So, you can also say that you have 4 units of $0.25.

If you do anything with money, you are likely doing these conversions, but maybe without knowing it.

Hope this example helps.(3 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.