Shoudn't the fraction -2/-1 be less than one?

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Discussion Overview

The discussion revolves around the mathematical interpretation of the fraction -2/-1 and whether it should be considered less than one. Participants explore the implications of dividing negative numbers and the rules governing fractions, particularly in relation to the signs of the numerator and denominator.

Discussion Character

  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants argue that since -2 is less than -1, the fraction -2/-1 should be less than one, but they acknowledge that multiplying both numerator and denominator by -1 results in 2/1, which is greater than one.
  • Another participant points out that the rule stating a fraction is less than one if the numerator is less than the denominator only applies when the denominator is positive.
  • One participant suggests that the negative nature of the numbers changes the interpretation, indicating that the rules for positive fractions do not directly apply to negative fractions.
  • There is a reiteration that the numerator being smaller than the denominator does not determine the fraction's value when both are negative, as the fraction represents a ratio rather than a simple comparison.
  • Some participants express confusion over the application of inequality rules when dividing by negative numbers, leading to a misunderstanding of the fraction's value.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the interpretation of the fraction -2/-1, with multiple competing views on how to apply the rules of fractions and inequalities involving negative numbers.

Contextual Notes

Some participants highlight the importance of considering the signs of the numerator and denominator when evaluating fractions, indicating that the discussion is limited by differing interpretations of mathematical rules regarding negative numbers.

kay
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Because technically, the numerator is smaller than the denominator as −2<−1

I know it's an extremely stupid question.

I mean I know that I can just multiply −1 to the numerator and the denominator and I'll get 2/1 which is greater than one.

But what exactly is happening here?

A number that is supposed to be less than one is coming out to be greater than one;double, to be precise.
 
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kay said:
Because technically, the numerator is smaller than the denominator as −2<−1

I know it's an extremely stupid question.

I mean I know that I can just multiply −1 to the numerator and the denominator and I'll get 2/1 which is greater than one.

But what exactly is happening here?

A number that is supposed to be less than one is coming out to be greater than one;double, to be precise.
Starting with

-2<-1

if you divide both sides by the negative number -1, you're supposed to reverse the inequality sign. So

-2&lt;-1

\frac{-2}{-1}&gt;\frac{-1}{-1}=1

Also, the numerator being smaller than the denominator isn't the rule for numbers to turn out smaller than 1. The numerator is TWICE the size of the denominator, hence the result should be 2. Fractions are about ratios, not comparisons.
 
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You appear to be using a rule that "a fraction is less than one if the numerator is less than the denominator". That is only true if the denominator is positive.

If n< d then n/d< 1 requires that d be positive.
 
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I think you're seeing the negative side of real numbers just as you do the positive sides. What you described goes for the positive side, but conversely for the negative side. The neagative is opposite of the positive. So if small-number-numerator-over-big-number-denominator is a proper fraction on the positive side, then it's an improper fraction on the negative, that is with the same small-number-numerator-over-big-number-denominator arrangement.
 
N
Mentallic said:
Also, the numerator being smaller than the denominator isn't the rule for numbers to turn out smaller than 1. The numerator is TWICE the size of the denominator, hence the result should be 2. Fractions are about ratios, not comparisons.
No, when numerator is smaller than denominator then the fraction is always less than 1. Here, numerator 2>denominator1 so, 2/1 is greater than 1
 
And -2<-1

Yeah, I mistook. The converse relation for negative sides
 
kay said:
Shoudn't the fraction -2/-1 be less than one?
No. Do the division, keeping in mind that when both the numerator and denominator are the same sign, the value of the fraction is positive.
$$\frac{-2}{-1} = 2 > 1$$

If you are using a "rule" that ignores the above property of division, that rule is bogus.

The question has been asked and answered, so closing this thread.
 
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