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The Gallup organization found that 29% of Americans own a cat as a pet. Round all probabilities to four decimal places. a) Find the probability that 7 Americans own a cat as a pet. b) Find the probability that ALL 7 Americans DO NOT own a cat as a pet. c) Find the probability that at least one of 7 Americans owns a cat as a pet. Question Help: □ Message instructor D Post to forum

User Jai Techie
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Final answer:

a) The probability that 7 Americans own a cat as a pet is approximately 0.0027. b) The probability that ALL 7 Americans do not own a cat as a pet is approximately 0.9973. c) The probability that at least one of 7 Americans owns a cat as a pet is approximately 0.0027.

Step-by-step explanation:

a) To find the probability that 7 Americans own a cat as a pet, we use the binomial probability formula:



P(X = k) = (nCk) * p^k * (1-p)^(n-k)



Where n is the number of trials, k is the number of successful trials, p is the probability of success, and (nCk) is the binomial coefficient.



Plugging in the values, we have:



P(X = 7) = (7C7) * (0.29)^7 * (1-0.29)^(7-7)



Simplifying, we get:



P(X = 7) ≈ 0.0027



b) To find the probability that ALL 7 Americans do not own a cat as a pet, we simply calculate the complement of the probability that 7 Americans own a cat as a pet:



P(X = 0) = 1 - P(X = 7) = 1 - 0.0027 ≈ 0.9973



c) To find the probability that at least one of 7 Americans owns a cat as a pet, we calculate the complement of the probability that none of them own a cat:



P(X ≥ 1) = 1 - P(X = 0) = 1 - 0.9973

≈ 0.0027

User Tyler Morales
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