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A particular type of tennis racket comes in a midsize version and an oversize version. Sixty percent of all customers at a certain store want the oversize version.

Among ten randomly selected customers who want this type of racket, what is the probability that at least six want the oversize version?

User Feyyaz
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Final answer:

The probability that at least six out of ten randomly selected customers want the oversize version of a tennis racket is 0.63145608.

Step-by-step explanation:

To find the probability that at least six out of ten randomly selected customers want the oversize version of a tennis racket, we can use the binomial probability formula. The binomial probability formula is P(X=k) = C(n, k) * p^k * (1-p)^(n-k), where n is the number of trials, k is the number of successes, p is the probability of success, and C(n, k) is the number of combinations of n items taken k at a time. In this case, n = 10, k can be any value from 6 to 10, p = 0.6, and q = 1 - p = 0.4.

To find the probability that at least six want the oversize version, we need to calculate the probabilities for k=6, 7, 8, 9, and 10, and add them together.

P(X=6) = C(10, 6) * (0.6)^6 * (0.4)^(10-6) = 0.250822656

P(X=7) = C(10, 7) * (0.6)^7 * (0.4)^(10-7) = 0.214990848

P(X=8) = C(10, 8) * (0.6)^8 * (0.4)^(10-8) = 0.120932351

P(X=9) = C(10, 9) * (0.6)^9 * (0.4)^(10-9) = 0.038654608

P(X=10) = C(10, 10) * (0.6)^10 * (0.4)^(10-10) = 0.0060466176

Adding these probabilities gives us:

P(X>=6) = P(X=6) + P(X=7) + P(X=8) + P(X=9) + P(X=10) = 0.63145608

User Ronald Coarite
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