Question 1

Which probability calculator should I use for my problem?

Accepted Answer

Start by identifying your scenario type. Use the Single Event Calculator for one outcome, Two/Three Events Calculators for independent multiple events, Distribution Calculators when working with specific probability distributions (binomial, normal, etc.), Conditional Probability Calculator for dependent events, and Bayes' Theorem Calculator when updating probabilities with new evidence.

Question 2

What's the difference between discrete and continuous probability calculators?

Accepted Answer

Discrete calculators work with countable outcomes (number of successes, number of events) and use distributions like binomial or Poisson. Continuous calculators handle measurable quantities that can take any value in a range (time, weight, height) and use distributions like normal or exponential. If you can count your outcomes, use discrete; if you're measuring something, use continuous.

Question 3

When do I need a conditional probability calculator versus a joint probability calculator?

Accepted Answer

Use conditional probability when one event has already occurred and you want the probability of another event given that information (P(A|B) - 'A given B'). Use joint probability when you need the probability of both events occurring together, without assuming one has already happened (P(A ∩ B) - 'A and B together').

Question 4

Can these calculators help me learn probability or are they just for computing answers?

Accepted Answer

These calculators serve both purposes. They provide accurate computations for homework and real-world problems, but many also show step-by-step explanations of the formulas and logic. Use them to verify your manual calculations, explore how probability changes with different inputs, and build intuition about probability relationships.

Question 5

What is expected value and when should I calculate it?

Accepted Answer

Expected value is the long-run average outcome of a probability scenario. Calculate it when making decisions involving uncertain outcomes, such as evaluating gambling games, comparing investment options, pricing insurance, or any situation where you need to know the average result across many repetitions of a random process.

Basic Probability Calculators

Single Event Probability Calculator