EKS Posted January 3 Share Posted January 3 I just learned something kind of interesting. What is the quotient and remainder when dividing -5 by 3? Quote Link to comment Share on other sites More sharing options...
QueenCat Posted January 3 Share Posted January 3 -1.66666666667 Quote Link to comment Share on other sites More sharing options...
wathe Posted January 3 Share Posted January 3 (edited) -2 R1, I think. dividend = divisor * quotient + remainder -5 = 3(-2)+1 (It's been a while since I've had to think about this!) Edited January 3 by wathe Quote Link to comment Share on other sites More sharing options...
EKS Posted January 3 Author Share Posted January 3 14 minutes ago, wathe said: -2 R1, I think. dividend = divisor * quotient + remainder -5 = 3(-2)+1 (It's been a while since I've had to think about this!) That's right! The remainder is positive. I'm pretty sure that in all of the elementary math materials we used, we never encountered this. I think it must be because negative number division is typically introduced after kids stop dealing with remainders. I just learned this from my abstract algebra text. 1 Quote Link to comment Share on other sites More sharing options...
maize Posted January 3 Share Posted January 3 Why is it done this way? Quote Link to comment Share on other sites More sharing options...
City Mouse Posted January 3 Share Posted January 3 This doesn’t generally come up in elementary math because division with remainders is only taught through 4th or maybe early 5th grade. By the time division with negative numbers is introduced, students are diving to decimals rather than remainders. Quote Link to comment Share on other sites More sharing options...
EKS Posted January 3 Author Share Posted January 3 5 minutes ago, maize said: Why is it done this way? Convention--though a google search makes me think that it sometimes changes depending on the application. Quote Link to comment Share on other sites More sharing options...
Ausmumof3 Posted January 3 Share Posted January 3 So can it not also be -1 remainder -2 or is that just not how it’s done? Because if we divided into a fraction it would be -1 2/3 not -2 and positive 1/3? I’ve never come across this before. Quote Link to comment Share on other sites More sharing options...
Drama Llama Posted January 3 Share Posted January 3 1 hour ago, EKS said: Convention--though a google search makes me think that it sometimes changes depending on the application. I have never seen remainders used in a math problem for kids who are far enough along to be working with negative numbers, unless there's a context. But if there's a context, then you need to use the context to understand whether a positive or negative remainder makes sense. Quote Link to comment Share on other sites More sharing options...
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