Division resulting in decimals
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 5/2 is. In the past, you might have said, "Hey, 2 times 2 is 4, and then you have 1 left over," and so you might have said something like this: "This is 2 with a remainder of 1."
But now we don't want that. We want to say, "Hey, how many times can it go in, and what's left over?" We want to know exactly how many times can 2 go into 5, 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. There's many ways that we can approach this. One way is to realize that 5 divided by 2 we can re-express as 5 divided by 2 or as 5 halves. And 5 halves is the same thing as 4 plus 1 over 2, which is the same thing as 4 halves plus 1/2. This is the same thing as 4 halves is... let me do that in a different color.
This part over here is 2, and then you have this 1/2. So it's the same thing as 2 and 1/2. And if we were to express that as a decimal, that's going to be equal to 2.
Now, how many tenths is equal to 1/2? Well, 5 tenths is equal to 1/2, so 5 divided by 2, you could say, is 2.5.
Now another way that you could approach this is you say 5 divided by 2 is the same thing as 50 tenths divided by 2. So let me use a different color here.
Instead of a 5, I could say 5 is the same thing as 50 tenths. 50 tenths divided by divided by 2, and so if I have 50 of something and if I were to divide it by 2, 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... I could put some place values here. So we definitely have 5 tenths. I'll put that in the tenths place, and then 20 tenths.
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.