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Question 21906: A Complete Disjoint Partition and Global Mean Use the Same Law

On this page
  1. Original question and givens
  2. Definition and scope
  3. Step-by-step derivation
  4. Reverse checks
  5. Result
  6. This question review and source binding

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R0042-21906 · q-20261014-advance-20261109-r04-law-of-total-expectation-0006

Original question and givens

Use the complete normalized finite law masses=[1/15, 2/15, 12/15, 0/1], aligned values X=[5, 6, 8, 104] and complete disjoint partition=[[0, 1], [2, 3]] covering every atom. Values are integrable in this finite model. Cell order and atom order are retained; independence is not required. Conditional quotients require strictly positive cell mass. Give (partition, cell_masses, complete_disjoint_certificate, mean).

  • G001 — Use the complete normalized finite law masses=[1/15, 2/15, 12/15, 0/1], aligned values X=[5, 6, 8, 104] and complete disjoint partition=[[0, 1], [2, 3]] covering every atom. Values are integrable in this finite model. Cell order and atom order are retained; independence is not required. Conditional quotients require strictly positive cell mass. Give (partition, cell_masses, complete_disjoint_certificate, mean).

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.

Step-by-step derivation

S001 · implies

Before

source operation=totalexp-partition-audit;original snapshot and mathematics retained

After

explicit ordered source output fields=[partition, cell_masses, complete_disjoint_certificate, mean]

Conditions: none

Keep the original historical interface marker while listing ordered source fields without JavaScript.Tags are not additional evidence;fixed No markers retain their source claim scope.

Step identifiers and dependencies

Rule: source_ordered_interface_explicit_without_javascript · Uses: G001

S002 · calculation

Before

Total expectation complete original mass := sum(1/15, 2/15, 4/5, 0)

After

Total expectation complete original mass = 1

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S001

S003 · calculation

Before

Total expectation original atom0 weighted X := mul(1/15, 5)

After

Total expectation original atom0 weighted X = 1/3

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · calculation

Before

Total expectation original atom1 weighted X := mul(2/15, 6)

After

Total expectation original atom1 weighted X = 4/5

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S003

S005 · calculation

Before

Total expectation original atom2 weighted X := mul(4/5, 8)

After

Total expectation original atom2 weighted X = 32/5

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S004

S006 · calculation

Before

Total expectation original atom3 weighted X := mul(0, 104)

After

Total expectation original atom3 weighted X = 0

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S005

S007 · calculation

Before

Total expectation full original mean := sum(1/3, 4/5, 32/5, 0)

After

Total expectation full original mean = 113/15

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S006

S008 · implies

Before

ORIGINAL masses=[1/15, 2/15, 4/5, 0],SIGNED values X=[5, 6, 8, 104];ORIGINAL cell order=[[0, 1], [2, 3]]

After

flattened original atom labels=[0, 1, 2, 3] cover EVERY atom exactly ONCE including null atoms;total mass=1;integrable finite mean=113/15;NO independence premise

Conditions: none

The partition covers all original atoms,including null atoms,exactly once.Keep original cell order and source-normalized internal labels.X may be signed and is integrable in this finite model;independence is not required.

Step identifiers and dependencies

Rule: totalexp_same_law_complete_disjoint_partition_all_atoms · Uses: G001, S007

S009 · calculation

Before

Total expectation cell0 mass := sum(1/15, 2/15)

After

Total expectation cell0 mass = 1/5

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S008

S010 · calculation

Before

Total expectation cell0 numerator := sum(1/3, 4/5)

After

Total expectation cell0 numerator = 17/15

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S009

S011 · calculation

Before

Total expectation cell0 positive-mass conditional mean := div(17/15, 1/5)

After

Total expectation cell0 positive-mass conditional mean = 17/3

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S010

S012 · implies

Before

ORIGINAL cell index=0,atom labels=[0, 1];mass=1/5;weighted numerator=17/15

After

conditional quotient=17/3;positive denominator qualifies division

Conditions: none

Divide only for positive cell mass.In a null cell,all nonnegative atom masses are0,so the numerator is0 but0/0 remains undefined.Keep null rather than an asserted quotient0,including empty cells.

Step identifiers and dependencies

Rule: totalexp_cell_quotient_positive_mass_only_null_preserved · Uses: G001, S011

S013 · calculation

Before

Total expectation cell1 mass := sum(4/5, 0)

After

Total expectation cell1 mass = 4/5

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S012

S014 · calculation

Before

Total expectation cell1 numerator := sum(32/5, 0)

After

Total expectation cell1 numerator = 32/5

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S013

S015 · calculation

Before

Total expectation cell1 positive-mass conditional mean := div(32/5, 4/5)

After

Total expectation cell1 positive-mass conditional mean = 8

Conditions: none

Substitute the original roles,order and conditions term by term with exact arithmetic,not floating-point approximation.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S014

S016 · implies

Before

ORIGINAL cell index=1,atom labels=[2, 3];mass=4/5;weighted numerator=32/5

After

conditional quotient=8;positive denominator qualifies division

Conditions: none

Divide only for positive cell mass.In a null cell,all nonnegative atom masses are0,so the numerator is0 but0/0 remains undefined.Keep null rather than an asserted quotient0,including empty cells.

Step identifiers and dependencies

Rule: totalexp_cell_quotient_positive_mass_only_null_preserved · Uses: G001, S015

Reverse checks

  • S016 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S015 · premise_and_result_audit — Recompute Total expectation cell1 positive-mass conditional mean with exact rational arithmetic, not rounded decimals.
  • S014 · premise_and_result_audit — Recompute Total expectation cell1 numerator with exact rational arithmetic, not rounded decimals.
  • S013 · premise_and_result_audit — Recompute Total expectation cell1 mass with exact rational arithmetic, not rounded decimals.
  • 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 — Recompute Total expectation cell0 positive-mass conditional mean with exact rational arithmetic, not rounded decimals.
  • S010 · premise_and_result_audit — Recompute Total expectation cell0 numerator with exact rational arithmetic, not rounded decimals.
  • S009 · premise_and_result_audit — Recompute Total expectation cell0 mass with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S007 · premise_and_result_audit — Recompute Total expectation full original mean with exact rational arithmetic, not rounded decimals.
  • S006 · premise_and_result_audit — Recompute Total expectation original atom3 weighted X with exact rational arithmetic, not rounded decimals.
  • S005 · premise_and_result_audit — Recompute Total expectation original atom2 weighted X with exact rational arithmetic, not rounded decimals.
  • S004 · premise_and_result_audit — Recompute Total expectation original atom1 weighted X with exact rational arithmetic, not rounded decimals.
  • S003 · premise_and_result_audit — Recompute Total expectation original atom0 weighted X with exact rational arithmetic, not rounded decimals.
  • S002 · premise_and_result_audit — Recompute Total expectation complete original mass 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

([[0, 1], [2, 3]], [[0, 1/5], [1, 4/5]], Yes, 113/15)

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: f8cddf38bfc1c399aecde2438aee54b80ccb1cb936aab1c15c155b00a602ee25
  • candidate record SHA-256: 035e3cd7a149f6784be4386c299fdeeec2bf5b404c9250176dba0c7874678075
  • semantic review receipt SHA-256: dd44555041dfbb6fe9936aa00b9a5f8c5982c2784ef61dd0cbd5d1a303a49c1a
  • question-first witness SHA-256: 9a6011263f6ac53b9a1fd57addf2f3e2f6088b54802c539f332d689480dc2d17
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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