Tayste — public domain · Public Domain · Wikimedia Commons
Binomial = sum of n iid Bernoullis. The next question is 'how many trials until the first success?' — that's the Geometric distribution.
✓ Intro · expand
Try first (productive failure)
Before the worked example: spend 60 seconds taking your best shot at this.
A guess is fine — being briefly wrong about a problem makes the explanation
land harder when you read it. This appears once per tutorial; skip
if you already know the trick.
60s
✓ Try first · expand
Worked example
A free-throw shooter makes each shot independently with probability p = 0.6. They take n = 10 shots. Let X = number of makes. (a) Identify the distribution. (b) Compute E[X] and Var(X). (c) Compute P(X >= 8).
✓ Worked example · expand
Practice 1 of 3Type a fraction, decimal, or expression.
✓ Practice · expand
Reflection
Where does this distribution sit in the story chain — what question does it answer that the previous distribution couldn't? Try to recall the key moment formulas (mean, variance) without looking them up.
