# Question 8244: Scaled Rational Values and Order Direction

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This teaching derivation has second-context AI mathematical and bilingual semantic review, limited to the model and assumptions stated in this question. It has no human review or new Lean proof and does not promote the original question or MKO to Canonical truth.

R0015-08244 · q-20261012-advance-20261017-r04-order-relation-0094



## Original question and givens

Use the usual total order on R, restricted to exact rational inputs whose original denominators are positive. Output reduced fractions with positive denominators, retaining /1; do not extrapolate to arbitrary partial orders or complex numbers. a=6/3, b=7/2, t=0/3. Give (a, b, t, t*a, t*b, original comparison, scaled comparison, order-preserved/order-reversed/collapsed according to the sign of t).


- G001 — Use the usual total order on R, restricted to exact rational inputs whose original denominators are positive. Output reduced fractions with positive denominators, retaining /1; do not extrapolate to arbitrary partial orders or complex numbers. a=6/3, b=7/2, t=0/3. Give (a, b, t, t*a, t*b, original comparison, scaled comparison, order-preserved/order-reversed/collapsed according to the sign of t).





## Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.


- [mko-order-relation](https://ocme.evemisslab.com/en/mko/mko-order-relation/)





## Step-by-step derivation

S001 · impliesBefore

usual total order on R;all original denominators positive

After

closed endpoints included;negative scaling reverses;zero collapses

Conditions: none

These exact rationals use the usual real total order,not complex numbers or an arbitrary partial order.Original denominators must be positive;normalizing a negative input denominator does not waive that contract.

Step identifiers and dependenciesRule: real_rational_order_scope · Uses: G001





S002 · calculationBefore

scaled first value := mul(0, 2)

After

scaled first value = 0

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S001





S003 · calculationBefore

scaled second value := mul(0, 7/2)

After

scaled second value = 0

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S002





S004 · calculationBefore

original order left cross := mul(2, 2)

After

original order left cross = 4

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S003





S005 · calculationBefore

original order right cross := mul(7, 1)

After

original order right cross = 7

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S004





S006 · calculationBefore

original order cross residual := sub(4, 7)

After

original order cross residual = -3

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S005





S007 · impliesBefore

original order:fractions=[2/1, 7/2]

After

cross residual=-3;comparison=<

Conditions: none

Reduced denominators are positive,so the cross-difference sign determines order.Retain equality and use original indices separately to break equal-value sorting ties.

Step identifiers and dependenciesRule: rational_positive_denominator_comparison · Uses: G001, S006





S008 · calculationBefore

scaled order left cross := mul(0, 1)

After

scaled order left cross = 0

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S007





S009 · calculationBefore

scaled order right cross := mul(0, 1)

After

scaled order right cross = 0

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S008





S010 · calculationBefore

scaled order cross residual := sub(0, 0)

After

scaled order cross residual = 0

Conditions: none

Substitute the source data exactly in the stated operand order;division requires a nonzero denominator.

Step identifiers and dependenciesRule: exact_rational_arithmetic · Uses: G001, S009





S011 · impliesBefore

scaled order:fractions=[0/1, 0/1]

After

cross residual=0;comparison==

Conditions: none

Reduced denominators are positive,so the cross-difference sign determines order.Retain equality and use original indices separately to break equal-value sorting ties.

Step identifiers and dependenciesRule: rational_positive_denominator_comparison · Uses: G001, S010





S012 · impliesBefore

scale=0/1;old comparison=<

After

new comparison==;direction=merged

Conditions: none

The direction label depends on the scale's sign.Positive preserves,negative reverses,and zero collapses both values to0 even if originally equal.Equality remains equality under negative scaling.

Step identifiers and dependenciesRule: order_scale_sign_three_cases · Uses: G001, S011









## Reverse checks


- S012 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S011 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S010 · premise_and_result_audit — Recompute scaled order cross residual with exact rational arithmetic, not rounded decimals.
- S009 · premise_and_result_audit — Recompute scaled order right cross with exact rational arithmetic, not rounded decimals.
- S008 · premise_and_result_audit — Recompute scaled order left cross with exact rational arithmetic, not rounded decimals.
- S007 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
- S006 · premise_and_result_audit — Recompute original order cross residual with exact rational arithmetic, not rounded decimals.
- S005 · premise_and_result_audit — Recompute original order right cross with exact rational arithmetic, not rounded decimals.
- S004 · premise_and_result_audit — Recompute original order left cross with exact rational arithmetic, not rounded decimals.
- S003 · premise_and_result_audit — Recompute scaled second value with exact rational arithmetic, not rounded decimals.
- S002 · premise_and_result_audit — Recompute scaled first value with exact rational arithmetic, not rounded decimals.
- S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.





## Result

(2/1, 7/2, 0/1, 0/1, 0/1, <, =, collapsed)

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.





## This question review and source binding

Review date: 2026-10-26

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
- input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
- original question SHA-256: 918171ed520a9a45c891ba190be4d875fd7645d4af19db320d3c3f27b4c61fe2
- candidate record SHA-256: 6d36a0d41cce40260e82aeaaf60c1baf126dd0b57db0176e68eda220f8b9964d
- semantic review receipt SHA-256: 6ecad9d909199221a07e923f87425e80b3bdec3eed46fe5910d04fca694cae18
- question-first witness SHA-256: e8f00458977a09493b5f9f05ab9e6feec72debaf4c7d1c609d1fc95900a35a1b
- Lean: NOT_RUN · human review: NOT_PERFORMED

[Same-source full JSON](https://ocme.evemisslab.com/data/question-derivations/questions/q-20261012-advance-20261017-r04-order-relation-0094.json)




