Divide whole numbers with decimal quotients: 5÷2
About this video
This video shows how to divide 5 by 2 and get an exact decimal answer instead of a remainder. It uses two methods: rewriting 5 ÷ 2 as the fraction 5/2 = 2 1/2 = 2.5, and rewriting 5 as 50 tenths so that 50 tenths ÷ 2 = 25 tenths = 2.5.
You'll be able to
- divide two whole numbers and write the quotient as a decimal.
- rewrite a division like 5 ÷ 2 as a fraction and a mixed number.
- rewrite a whole number as tenths to help me divide.
Key words
- quotient
- The result you get when you divide.
- remainder
- The amount left over when one number doesn't divide another evenly.
- tenths
- Parts you get when one whole is split into 10 equal pieces; 0.1 is one tenth.
- decimal
- A way of writing numbers using place value to the right of the decimal point, like 2.5.
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.
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