Fraction & Percent Toolkit

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Mathematics

Tranche

calibration-1

Evidence ID

offline/source boundary

Ledger rows

1

No ledger note is attached.

Review findings

The empty honest_label is a concern: the catalog entry should either provide the missing formulas and validation behavior or honestly limit its claim to fraction reduction and percent change. The current specification is not sufficient for implementation verification.

Formula and scope findings

• The specification only defines fraction reduction and percent change, but claims mixed-to-improper conversion, improper-to-mixed conversion, LCD addition, percent-of, markup, discount, and ratio splitting without providing formulas for them.
• The reduction expression "a/gcd:b/gcd" is ambiguous unless gcd is explicitly defined as gcd(|a|,|b|), with the result interpreted as (a/g):(b/g).
• Percent change requires the original value to be nonzero; this domain constraint is missing.
• No formula is provided for decimal conversion or conversion from a decimal result to a percent result.
• No rules are given for sign normalization, denominator positivity, mixed-number validity, LCD selection, or rounding.

Unit assumptions

• Fractions, ratios, and percentage calculations are dimensionless unless an instrument field explicitly supplies physical units.
• Percent inputs are interpreted as numeric percentage points: 15 means 15%, and calculations convert it to 0.15 when multiplying a quantity.
• Percent change uses old as the baseline: (new-old)/old × 100, with old != 0.
• Markup and discount percentages are applied multiplicatively: price × (1 + rate) and price × (1 - rate).
• Ratio splitting assumes the total is divided according to nonnegative ratio parts and that the ratio-part sum is nonzero.
• Decimal outputs shown as repeating values are mathematical representations; the required display precision is unspecified.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

A zero old-value percent-change input produces an undefined division by zero. The instrument must reject it or explicitly return undefined; any finite numeric result would be incorrect.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "operation": "simplify_fraction",
    "numerator": 84,
    "denominator": 126
  },
  "expected_outputs": {
    "simplified_fraction": "2/3",
    "decimal": "0.666666...",
    "percent": "66.666666...%"
  },
  "working": "gcd(84,126)=42. Reduce numerator: 84/42=2. Reduce denominator: 126/42=3. Therefore 84/126=2/3. Decimal: 2 ÷ 3 = 0.666666.... Percent: (2 ÷ 3) × 100 = 66.666666...%."
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche2/batch10-output.jsonl
• BOUNDARY_HAZARD_CATALOG.json