Distributions and testing
Lesson 1 of 10
Introduction
The binomial distribution
Objective. Model repeated independent trials with X ~ B(n, p).
- 1. Learn
- 2. Worked example
- 3. Practice
- 4. Feedback
- 5. Continue
Learn: the key idea
Binomial applies when there is a fixed number of independent trials, each with two outcomes and constant probability.
Worked example
X ~ B(10, 0.3). Find P(X = 2).
- 1P(X = 2) = C(10,2) × 0.3² × 0.7⁸.
- 245 × 0.09 × 0.05765.
Answer: ≈ 0.233
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