NUMB3RS - Season 2 - "Mind Games" - Right or Wrong
Topic: The Binomial Theorem | Complexity: Algebra 2 / Pre-Calculus / Statistics
Activity Introduction
In the NUMB3RS episode "Mind Games," a psychic shocks Charlie by incorrectly guessing the color (black or red) of 25 cards in a row. As Charlie's colleague Larry point outs, "the probability of getting them all wrong is the same as getting them all right." In this activity, we will apply the Binomial Theorem to find the probability of correctly guessing outcomes for a series of events.
Step 1: Expanding Three Guesses
For each card guessed, the outcome is either right () or wrong (). Since the order of guesses does not matter for the final tally, the overall expansion of guessing three cards is represented by:
Because the card is equally likely to be red or black, the probability of guessing correctly is , and guessing incorrectly is . Note that .
Use this expansion to find the probability of guessing exactly 2 cards correctly and 1 card incorrectly.
Calculate the probability of guessing exactly 2 of the 3 cards correctly ():
Hint
Substitute $R = 0.5$ and $W = 0.5$ into the term $3R^2W$.
Binomial Distribution Sandbox
Adjust trials and success probability to explore how the distribution curve shifts.
Run Guessing Simulation
Run 1,000 empirical trials to observe how frequencies converge.