17. A school district is assumed to have 8,000 5th graders. The average weight of a...

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17. A school district is assumed to have 8,000 5th graders. The average weight of a 5th grader is 75 pounds, with a standard deviation of 20 pounds. If a random sample of 50 students is drawn, find the probability that the average weight of a student from the drawn sample will be between 60 and 70 pounds. A) 0.039 B) 0.175 C) 0.401 D) 0.227 E) 0.773 18. The mean and the standard deviation of a normally distributed population is 30.5 and 5.0, respectively. Find the probability that the mean of a sample of size 25 drawn from this population is greater than a value between 28 and 30. A) 0.50 B) 0.15 C) 0.30 D) 0.00 E) 0.46 19. 60% of all Americans owned an iPhone just after its release in 2007. Marie believes that this proportion may not be true for the state of Georgia. She takes a random sample of 1,850 people and finds that only 800 have an iPhone. Find the probability of getting a sample proportion is less than 0.4 if the population proportion is really 0.6. A) 1.00 B) 0.40 C) 0.60 D) 0.0024 E) 0.9976 20. A sample of 30 graduating college students is selected and eight of them plan to pursue higher education. If we consider another random sample of size 40 students, what is the probability that 20 percent or more of them will pursue higher education? A) 0.27 B) 0.20 C) 0.06 D) 0.80 E) 0.19 17. A school district is assumed to have 8,000 5th graders. The average weight of a 5th grader is 75 pounds, with a standard deviation of 20 pounds. If a random sample of 50 students is drawn, find the probability that the average weight of a student from the drawn sample will be between 60 and 70 pounds. A) 0.039 B) 0.175 C) 0.401 D) 0.227 E) 0.773 18. The mean and the standard deviation of a normally distributed population is 30.5 and 5.0, respectively. Find the probability that the mean of a sample of size 25 drawn from this population is greater than a value between 28 and 30. A) 0.50 B) 0.15 C) 0.30 D) 0.00 E) 0.46 19. 60% of all Americans owned an iPhone just after its release in 2007. Marie believes that this proportion may not be true for the state of Georgia. She takes a random sample of 1,850 people and finds that only 800 have an iPhone. Find the probability of getting a sample proportion is less than 0.4 if the population proportion is really 0.6. A) 1.00 B) 0.40 C) 0.60 D) 0.0024 E) 0.9976 20. A sample of 30 graduating college students is selected and eight of them plan to pursue higher education. If we consider another random sample of size 40 students, what is the probability that 20 percent or more of them will pursue higher education? A) 0.27 B) 0.20 C) 0.06 D) 0.80 E) 0.19