# Concept derivation guides

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Concept guide



## [Rational number: different fraction representations of one rational, cross-multiplication and reduction](/en/derivations/derivation-mko-rational-number-01/?from=%2Fen%2Fderivations%2F%3Fq%3Dmko-rational-number)

Using the MKO's definition (there are integers p, q with q≠0 and x=p/q), prove that 6/(−8), −3/4 and 9/(−12) represent the same rational number, and reduce 6/(−8) exactly to the canonical form −3/4; prove 2/3≠3/5 by cross-multiplication; show that '5/0' denotes no number; show that the finite decimal −1.25=−5/4 and the integer 7=7/1 are rational; and, with positive denominators, prove −3/4<−2/3 by cross-multiplication.

Rational number

derivation-mko-rational-number-01





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