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Thời điểm hiện tại:0:00Tổng thời gian:3:43

let's tackle a slightly more interesting division problem so we're going to take 280 and divide it by 5 and I encourage you to pause this video and try to apply the technique that we've seen in previous video to try to figure out what 280 divided by 5 is so let's have our go at it so we could rewrite this we've already seen this as 280 divided by divided by 5 so the first question we can ask ourselves is how many times does 5 go into 2 well 5 doesn't go into 2 at all it goes 0 times 0 times 5 is 0 and then we subtract 2 minus 0 is 2 and now we can bring down the next digit which in this case is an 8 and so we can ask ourselves how many times does 5 go into 28 without going over it so we could think well if let's see 5 times 5 is 25 5 times 6 is 30 so 5 times 6 would go over to 28 so we would want to go back to 5 times 5 so 5 goes into 28 5 times 5 times 5 is 25 and you subtract 28 minus 25 is 3 and now let's bring down the next digit in this case the digit is a zero so how many times does 5 go into 30 well it goes exactly 6 times we've already talked about that 6 times 5 is 30 we subtract and we have nothing we have nothing left over so we just figured out that 280 divided by 5 is equal to is equal to 56 now why did this work well the first way to think about it this was actually 200 and we were thinking about do we put anything in the hundreds place here so one way of thinking about it how many hundreds of times does 5 go into 200 and it doesn't go any multiples of 100 and if that's a little confusing don't worry too much about it but I want you to really think about deeply about the place notation but then we were able to again extend it to instead of just 200 but then 280 this 28 right over here if you think about it this 2 is in the hundreds place this 8 is in the tens place so this is really representing 280 and we said how many tens of times I'll go into 280 well it goes five tens times or it goes 50 times 50 times five is 250 when you subtract 250 from 280 you got 30 and there was no other things in the ones place here so we just have to figure out how many times does 5 go into 30 so hopefully that gives you a sense of what's actually happening behind this little process this little it's not just magic we're really just keeping track of place value here the other thing I want to show you is that we didn't necessarily have to write this zero here another way of computing it we could have said 280 divided by 5 we could have said how many times does 5 go into 2 what doesn't go any times so let's just think about 5 go into 28 5 going into 28 well 5 goes into 28 5 times 5 times 5 is 25 subtract 28 minus 25 is 3 bring down the 0 5 goes into 30 6 times 6 times 5 is 30 and we have nothing left over and again what we were really saying is that 5 doesn't go into 2 200 any hundreds of times if this was a 500 you could say hey is going to go in at 100 times but instead we go well what about five going into 280 well it goes 50 times 50 times 5 is 250 280 minus 250 is 35 goes into 30 6 times so hopefully that makes a little bit of sense