Mathematics · Probability

Posterior Probability from Odds unit odds baseline Solver

Rearrange the posterior probability from odds relationship and solve for unit odds baseline.

Runs locally
Your numbers

Inputs and results stay in this browser. Change one value at a time to explore the relationship.

Your inputCalculatedPassed forward in chains
unit odds baseline1
Reconstructed posterior probability0.75

Calculation steps

  1. Use b=a(1−c)/c with posterior probability=0.75 and posterior odds in favour=3.
  2. unit odds baseline=1.
  3. Substitution into c=a/(a+b) reconstructs 0.75.

Understand Posterior Probability from Odds: solve unit odds baseline

One idea, three depths

Choose how deeply to explain Posterior Probability from Odds: solve unit odds baseline

Posterior Probability from Odds: solve unit odds baseline: Rearrange the posterior probability from odds relationship and solve for unit odds baseline.

Age 5Explain it to a 5-year-oldStart with a picture

Imagine using Posterior Probability from Odds: solve unit odds baseline to answer this question: rearrange the posterior probability from odds relationship and solve for unit odds baseline? Enter posterior probability and posterior odds in favour; the calculator shows unit odds baseline. For example: posterior odds in favour=3 and unit odds baseline=1 produce posterior probability=0.75. The answer tells you unit odds baseline.

Age 15Explain it to a 15-year-oldConnect it to the formula

Probability equals favourable odds divided by favourable odds plus the baseline odds against. This page isolates unit odds baseline and verifies it in the original relationship. The rule is b=a(1−c)/c. Its input values are posterior probability, posterior odds in favour, and the main result is unit odds baseline. For example: posterior odds in favour=3 and unit odds baseline=1 produce posterior probability=0.75.

CollegeExplain it at college levelState the model precisely

This calculator evaluates the stated posterior probability from odds: solve unit odds baseline relation over the valid real-number domain stated below. The implemented relation is b=a(1−c)/c, evaluated from posterior probability, posterior odds in favour to produce unit odds baseline. Probability equals favourable odds divided by favourable odds plus the baseline odds against. This page isolates unit odds baseline and verifies it in the original relationship. For ordinary odds use baseline one; odds must be nonnegative.

Inputs and valid domain

  • posterior probability must be a finite real number.
  • posterior odds in favour must be a finite real number.

Important boundary: For ordinary odds use baseline one; odds must be nonnegative.

The formula

b=a(1−c)/c

How the calculator works through it

It substitutes posterior probability, posterior odds in favour into the formula and exposes every numerical step above. The main output is unit odds baseline, accompanied by Reconstructed posterior probability.

Read the result correctly

The unit odds baseline is the direct answer to “rearrange the posterior probability from odds relationship and solve for unit odds baseline.” Read it with the units shown beside the inputs; a sign, angle, percentage or rate changes what the number means.

A worked check

posterior odds in favour=3 and unit odds baseline=1 produce posterior probability=0.75.

Where this model stops being reliable

For ordinary odds use baseline one; odds must be nonnegative.

Learn it by changing one value

Begin with the worked example, then change one value while keeping the others fixed. Compare the new result and calculation steps to identify which part of the formula changed.

Dictionary terms behind this calculator

Before studying the codeWhat you should know firstUse the calculator immediately, or check the foundations before reading the implementation.

These foundations help you understand why Posterior Probability from Odds: solve unit odds baseline works. They never block the calculator, and “optional” means useful context rather than a hidden requirement.

Hard requirements

  • Reading formulas and substituting values

    Posterior Probability from Odds: solve unit odds baseline uses b=a(1−c)/c. You need to recognise what each side represents before substituting the stated inputs or rearranging the relationship.

    Review this foundation about 4 min

Strong support

  • Probability as a modelled proportion

    Probability rules are needed to interpret what the Posterior Probability from Odds: solve unit odds baseline result says about possible outcomes.

    Review this foundation about 5 min

Optional enrichment

  • Ordered arrangements

    Counting ordered arrangements can extend Posterior Probability from Odds: solve unit odds baseline to more detailed sample spaces and event models.

    Review this foundation about 5 min
Learn the missing foundationsI already know these — show the code

Mathematics → algorithm → program

Implement this calculation in code

These are direct reference implementations of the calculator's principal relationship and first output. They run locally and include a small known-answer check where the language supports it.

Algorithm

  1. Read posterior probability, posterior odds in favour.
  2. Evaluate the principal relationship: b=a(1−c)/c.
  3. Return unit odds baseline and check the domain conditions described above.
Python
            from math import *

def posterior_odds_probability_solve_b(c, a) -> float:
    return ((a * (1.0 - c)) / c)

assert abs(posterior_odds_probability_solve_b(0.75, 3) - 1) < 1e-6 * max(1.0, abs(1))
          
Current calculator valuesUpdates when you change an input above.
              
            
C
            #include <assert.h>
#include <math.h>

double posterior_odds_probability_solve_b(double c, double a) {
    return ((a * (1.0 - c)) / c);
}

int main(void) {
    const double expected = 1;
    const double actual = posterior_odds_probability_solve_b(0.75, 3);
    assert(fabs(actual - expected) < 1e-6 * fmax(1.0, fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
C++
            #include <cassert>
#include <cmath>
#include <numbers>

double posterior_odds_probability_solve_b(double c, double a) {
    return ((a * (1.0 - c)) / c);
}

int main() {
    constexpr double expected = 1;
    const double actual = posterior_odds_probability_solve_b(0.75, 3);
    assert(std::fabs(actual - expected) < 1e-6 * std::fmax(1.0, std::fabs(expected)));
}
          
Current calculator valuesUpdates when you change an input above.
              
            
Linux x86-64 assembly

x86-64 NASM · System V ABI · Linux · SSE2 with libm where required

            ; double posterior_odds_probability_solve_b(double c, double a)
; Linux x86-64 NASM · System V ABI · first eight doubles in xmm0–xmm7
global posterior_odds_probability_solve_b
section .text

posterior_odds_probability_solve_b:
    push rbp
    mov rbp, rsp
    sub rsp, 48
    movsd [rbp-8], xmm0
    movsd [rbp-16], xmm1
    mov rax, 0x3ff0000000000000
    movq xmm0, rax
    movsd [rbp-48], xmm0
    movsd xmm0, [rbp-48]
    subsd xmm0, [rbp-8]
    movsd [rbp-40], xmm0
    movsd xmm0, [rbp-16]
    mulsd xmm0, [rbp-40]
    movsd [rbp-32], xmm0
    movsd xmm0, [rbp-32]
    divsd xmm0, [rbp-8]
    movsd [rbp-24], xmm0
    movsd xmm0, [rbp-24]
    leave
    ret
          
Current calculator valuesUpdates when you change an input above.
              
            
MATLAB
            function result = posterior_odds_probability_solve_b(c, a)
    result = ((a * (1.0 - c)) / c);
end
          
Current calculator valuesUpdates when you change an input above.
              
            
Wolfram Language
            ClearAll[mwCalculate];
mwCalculate[c_, a_] := ((a * (1.0 - c)) / c);
          
Current calculator valuesUpdates when you change an input above.
              
            

Continue in mathematical software

The downloaded file includes your current inputs and first calculated result. It is created locally.

Floating-point answers can differ slightly by language, compiler and processor. Compare within a suitable tolerance rather than assuming every decimal representation will be identical.

Supporting sourcesAcademic referencesPrimary standards, textbooks and complete citations

Standards, reading and academic references

Use the calculator as the worked interaction, then consult the primary standards and academic textbooks listed below. MW SysArc links to the original sources; the explanation on this page is original and does not reproduce them.

Introductory Statistics 2e

Read the free OpenStax statistics textbook
Cite this book
APA 7
Illowsky, B., & Dean, S. (2023). Introductory statistics 2e. OpenStax. https://openstax.org/books/introductory-statistics-2e/pages/1-introduction
MLA 9
Illowsky, Barbara, and Susan Dean. Introductory Statistics 2e. OpenStax, 2023, https://openstax.org/books/introductory-statistics-2e/pages/1-introduction.
Chicago author-date
Illowsky, Barbara, and Susan Dean. 2023. Introductory Statistics 2e. Houston, TX: OpenStax. https://openstax.org/books/introductory-statistics-2e/pages/1-introduction.

OpenStax entries are free to read online. Follow the licence shown on each linked source before redistributing or adapting its content.

Reuse the page responsiblyCite this pageAPA, MLA, Chicago, Harvard, BibTeX and RIS

These formats cite this calculator page itself. They are separate from the academic references above, which support the mathematical method and terminology.

APA 7

MW SysArc. (2026, July 21). Posterior Probability from Odds unit odds baseline Solver. MW SysArc Tools. https://math.mwsysarc.com/probability/posterior-odds-probability-unit-odds-baseline-solver

MLA 9

MW SysArc. “Posterior Probability from Odds unit odds baseline Solver.” MW SysArc Tools, 21 July 2026, https://math.mwsysarc.com/probability/posterior-odds-probability-unit-odds-baseline-solver. Accessed 31 Aug. 2026.

Chicago 17

MW SysArc. “Posterior Probability from Odds unit odds baseline Solver.” MW SysArc Tools. Published July 21, 2026. Accessed August 31, 2026. https://math.mwsysarc.com/probability/posterior-odds-probability-unit-odds-baseline-solver.

Harvard

MW SysArc (2026) ‘Posterior Probability from Odds unit odds baseline Solver’, MW SysArc Tools. Published 21 July 2026. Available at: https://math.mwsysarc.com/probability/posterior-odds-probability-unit-odds-baseline-solver (Accessed: 31 August 2026).

BibTeX and RIS records

BibTeX

@misc{mwsysarc_posterior_odds_probability_solve_b_2026,
  author = {{MW SysArc}},
  title = {Posterior Probability from Odds unit odds baseline Solver},
  howpublished = {MW SysArc Tools},
  year = {2026},
  url = {https://math.mwsysarc.com/probability/posterior-odds-probability-unit-odds-baseline-solver},
  note = {Published July 21, 2026; accessed August 31, 2026}
}

RIS

TY  - ELEC
AU  - MW SysArc
TI  - Posterior Probability from Odds unit odds baseline Solver
T2  - MW SysArc Tools
PY  - 2026
DA  - 2026-07-21
Y2  - 2026-08-31
UR  - https://math.mwsysarc.com/probability/posterior-odds-probability-unit-odds-baseline-solver
N1  - Published July 21, 2026
ER  -

Clear answers

Frequently asked questions

What does the Posterior Probability from Odds: solve unit odds baseline do?

Rearrange the posterior probability from odds relationship and solve for unit odds baseline.

How does the Posterior Probability from Odds: solve unit odds baseline work?

The calculator applies b=a(1−c)/c. Probability equals favourable odds divided by favourable odds plus the baseline odds against. This page isolates unit odds baseline and verifies it in the original relationship.

What can I learn from the Posterior Probability from Odds: solve unit odds baseline?

It connects the mathematical rule to your chosen numbers and shows each calculation step. Change one input at a time to see how the result responds.

Does MW SysArc receive or store what I enter?

No. The calculation runs locally in your browser. MW SysArc does not receive or store your calculation inputs.

How should I use the result?

Use the steps to understand the method, then verify important school or professional work using the notation and rounding rules required in your setting.

Last reviewed . Calculations tested .

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