Finite Chapter 8.2

# Finite Chapter 8.2 - 5 Suppose 3% of Americans age 65 to 74...

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Math 120 SP08 SBrodnick 1 1 8.2 : Bernoulli Trials & Binomial Random Variables 2 * Bernoulli Trial : experiment that has exactly 2 possible outcomes – a success and a failure (distribution is Binomial ) * Prob. of success is p Prob. of failure is q = 1 – p * For example, Toss a coin; you get H or you don’t Throw a dart; you get a bull’s-eye or you don’t Choose a random ISU student; he or she is taking Math 120 or isn’t 3 Examples : Roll a die 3 times 1. Prob. of exactly 1 six 2. Prob. of exactly 2 sixes * In general, for n Bernoulli Trials, where x = # of successes, each with prob. p n x = # of failures, each with prob. q = 1 – p , P(X = x ) = n C x · p x · q n - x 4 Examples : Roll a die 10 times. Prob. of… 3. 4 fives 4. at least 8 twos 5. at most 9 fours A coin is tossed 6 times. Prob. of… 6. all tails 7. 4 tails 8. no more than 4 tails 9. at least 4 tails
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Unformatted text preview: 5 Suppose 3% of Americans age 65 to 74 have Alzheimer’s. Thirty people age 65 to 74 are selected at random. Prob. that… 10. 10 people have it 11. no one has it 12. at most 5 people have it Suppose 11% of Americans are left-handed. Fifty people are selected at random. Prob. that… 13. 10 people are left-handed 14. at least 2 people are 15. none of them are 16. at most 3 people are 8.2: Bernoulli Trials & Binomial Random Variables 6 To qualify for membership in Mensa, your IQ must be at least 132, putting you in the top 2% of the general population. Forty people are randomly chosen. 17. Prob. exactly 3 people qualify 18. Prob. at least 3 people qualify 19. 75% of a particular type of seed will germinate. Twelve seeds are planted. What is the prob. five will not germinate? 8.2: Bernoulli Trials & Binomial Random Variables...
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## This note was uploaded on 04/07/2008 for the course MAT 120 taught by Professor Brodnick during the Spring '08 term at Illinois State.

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