Chatty reference · stats1 week 5

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2026-08-16T00:00:00.000Z
Python Week 1: the first filter for runtime behavior
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Python Week 1: the first filter for runtime behavior

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ChatGPT archive slice for week 5. # 25.

25. Stats W5 — Counting

Concepts:
  • Addition rule
  • Multiplication rule
  • Factorials
Factorial:
n!=n(n−1)(n−2)⋯1n!=n(n-1)(n-2)\cdots1

Addition rule

Use when alternatives are mutually exclusive:
N=N1+N2+⋯N=N_1+N_2+\cdots

Multiplication rule

Use for sequential choices:
N=N1N2⋯N=N_1N_2\cdots
The real skill is recognizing whether a problem is additive or multiplicative.

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