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The Mathematics of the Lottery: Combinations and Expected Value

Why winning Powerball is 1 in 292 million and how expected value proves the house wins.

Combinations vs Permutations

A permutation counts arrangements where order matters; a combination counts selections where order does not matter.

Combination Formula: nCr = n! / [ r! (n - r)! ]

Calculating Total Powerball Combinations

Choose 5 white balls from 69: 69C5 = 11,238,513. Multiply by 26 red Powerball numbers: 11,238,513 × 26 = 292,201,338.

Jackpot Odds: 1 in 292,201,338 (0.000000342%)

Mathematical Expected Value (EV)

Expected value multiplies the probability of each prize by its payout, minus the ticket cost.

EV Formula: EV = Σ [ P(Prize_i) × Payout_i ] - Ticket_Cost

Why the House Always Wins

Even with massive billion-dollar jackpots, income tax withholdings (37%+) and the risk of splitting the jackpot with multiple winners keep long-term EV negative.

Mathematical Reality: Lotteries function as a voluntary probability tax.

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