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Calculadora de probabilidad.

Calculate probability, combinations, permutations, and odds

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01

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Calculated Result

16.67%
Decimal: 0.1667Fraction: 1/6Odds: 1:5

Formula

P(A) = 1 / 6

Steps

  • 1.Identify favorable outcomes: 1
  • 2.Identify total possible outcomes: 6
  • 3.Divide favorable by total: 1 ÷ 6 = 0.1667

FAQs

¿Cuál es la diferencia entre combinaciones y permutaciones?

Las combinaciones cuentan selecciones donde el orden no importa, mientras que las permutaciones cuentan arreglos donde el orden importa.

Cite this calculator

Canonical URL: https://mathify.one/es/math/probability

Cite as: Mathify. (2026). Calculadora de probabilidad. https://mathify.one/es/math/probability

Use Cases

Lottery and Game Odds

Determine the odds of winning a lottery or a game by calculating combinations and permutations. For example, find the number of possible 6-number combinations from 49 numbers.

Example: In a 6/49 lottery, the number of combinations is C(49,6) = 13,983,816.

Statistical Analysis and Experiment Design

Calculate probabilities for experiments, surveys, or quality control. Use binomial probability to find the likelihood of a certain number of successes in a sample.

Example: If 10% of products are defective, the probability of exactly 2 defects in a sample of 20 is about 0.285.

Frequently Asked Questions

What is the difference between combinations and permutations?
Combinations (nCr) count the number of ways to choose r items from n items without regard to order. Permutations (nPr) count arrangements where order matters. For example, choosing 3 letters from A, B, C: combinations give 1 (ABC), permutations give 6 (ABC, ACB, BAC, BCA, CAB, CBA).
How do I calculate the probability of multiple independent events?
For independent events, multiply their individual probabilities. For example, the probability of flipping heads (0.5) and rolling a 6 (1/6) is 0.5 × 1/6 ≈ 0.0833. This calculator can handle such calculations for you.
What is binomial probability used for?
Binomial probability calculates the chance of getting exactly k successes in n independent trials, each with the same success probability p. It's used in quality control, surveys, and any scenario with two outcomes (success/failure).

Tips & Common Mistakes

Tips

  • Ensure you understand whether order matters in your problem. If order matters, use permutations; if not, use combinations.
  • For multiple independent events, multiply their probabilities. For mutually exclusive events, add them.
  • When using binomial probability, verify that trials are independent and the success probability is constant.
  • Double-check your inputs for n and r: n must be greater than or equal to r, and both must be non-negative integers.

Common Mistakes to Avoid

  • Confusing combinations and permutations: using nPr when order doesn't matter, or vice versa.
  • Forgetting to convert percentages to decimals when entering probabilities (e.g., 25% should be 0.25).
  • Assuming events are independent when they are not, leading to incorrect probability multiplication.

Last updated: August 13, 2026