STEM PRACTICE AND EVIDENCE WORKBENCH
Calculate discrete growth or decay factors and repeated-change values, then audit learner factor and final-value claims.
Review output
Load the worked example to inspect realistic inputs, or enter anonymous classroom or laboratory evidence. Results remain in this browser tab until you copy or download them.
Transparent method
Growth factor equals one plus rate divided by 100; decay factor equals one minus it. Final value equals initial value times factor raised to the number of periods. Period zero uses factor to power zero and preserves the initial value. Supported means both one-period factor and compounded value agree. A correct factor with wrong final value points to repeated multiplication; a wrong factor points to percent direction or conversion. Review time units, domain, and assumptions.
Confirm the question, source, units, notation, response coding, model assumptions, and review threshold. Keep an unchanged copy of the original evidence.
Run the worked example, inspect every intermediate row, and compare it with a hand calculation, diagram, representation, or approved subject method.
Record the method, assumptions, units, classifications, and flagged rows. Verify the editable report independently before educational or laboratory use.
How to interpret the result
Use for repeated equal-period proportional change when learners may add a fixed amount or reverse decay direction. It does not fit rates from data, handle continuously compounded change, changing rates, negative populations, or causal forecasts.
Ten-percent growth for two periods changes 100 to 121, while 20-percent decay for three periods changes 200 to 102.4. Zero periods returns the initial value. The final 25-percent decay example should be 45 rather than the entered linear-thinking value 40.
Growth factor equals one plus rate divided by 100; decay factor equals one minus it. Final value equals initial value times factor raised to the number of periods. Period zero uses factor to power zero and preserves the initial value.
Supported means both one-period factor and compounded value agree. A correct factor with wrong final value points to repeated multiplication; a wrong factor points to percent direction or conversion. Review time units, domain, and assumptions.
Do not subtract the original percentage repeatedly as a fixed amount, use 0.25 as a 25-percent growth factor, reverse growth and decay, multiply rate by periods, or ignore period length. Build a table and graph to verify.
Learning boundary
This browser-local workbench applies only the disclosed rules. It cannot diagnose a learner, certify an experiment, or replace teacher, laboratory, and safety judgment.
Review checklist
Practical questions
No. Processing occurs in the current browser tab. Avoid personal information and retain authoritative records only in the approved school system.
No. It describes entered evidence under one disclosed rule. Review reasoning, uncertainty, access, and several evidence sources.
Treat it as an editable calculation aid. Show your own reasoning, cite required sources, and follow course and academic-integrity rules.
YOUR NIRMION
