Chapter 8 Day 4 Warm

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On the chapter 8 math test last year 27% of students got an A. If there are 45 students that take the test this year, find the following:

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What is the probability that 8 students get an A?

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What is the probability that at least 7 students get an A?

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What is the expected number of students that will get an A? What is the standard deviation?

9. μ = 1.25; σ = .9682 10.

A) μ = 4.5

B) σ = 1.7748

C) σ = 1.1619

11.

A) n = 20; p = .25 B) μ = 5

12.

A) .0687; .9313

B) μ = 2.4; σ = 1.3856

13.

A) on calculator

B) .1821

C) μ = 19.8; σ = .445

14.

A) .1; .9

B) .0999

C) .10001

C) .2023

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Geometric probability distribution function: geometpdf(p,x)

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Geometric cumulative distribution function: geometcdf(p,x) p is the probability of success x is the number of trials at which the first success occurs

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Aaron’s love potion works on 90% of women. What is the probability that the love potion will fail on the 6th girl he meets?

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What about on the 3rd girl?

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What is the probability that it takes more than 4 girls to fail?

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Suppose Roberto, a well-known major league baseball player finished last season with a .325 batting average. He wants to calculate the probability that he will get his first hit of the new season in his first at-bat. You define a success as getting a hit and define the random variable X = number of at-bats until Roberto gets his first hit.

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A. What is the probability that Roberto will get a hit on his first at-bat? What is the probability that it will take him at most 3 at-bats to get his first hit? What is the probability that it will take him more than 4 at-bats to get his first hit?