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4. The student enrollment at a local university is 53% female. Answer the following questionsbased on a sample of 32 randomly selected students.a. What is the probability that 20 of the students sampled are female? (4 pts)b. What is the probability that less than half of the sample is female? (6pts)

User MightyE
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1 Answer

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Let x be a random variable representing the number of female students enrolled in the university. This is a binomial distribution since there are two outcomes only. The student is either a male or a female

From the information given. the probability that the student is a female is

53/100 = 0.53

Thus, p = 0.53

The probability that the student is not a female, q is 1 - p

Thus, q = 1 - 0.53 = 0.47

a) We want to determine the probability of P(x = 20)

Given that n = 32, from the binomial distribution table,

p(x = 20) = 0.08

the probability that 20 of the students sampled are female is 0.08

b) Half of the sample is 32/2 = 16. The probability that less than half of the sample is a female is expressed as

p(x < 16) = 0.3

the probability that less than half of the sample is female is 0.3

User Ana Lava
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