BIOL 214 Quiz 3

Choose the discrete probability distribution.

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The Central Limit Theorem is important in statistics because _____.

• For any size sample, it says the sampling distribution of the sample mean is approximately normal

• For any population, it says the sampling distribution of the sample mean is approximately normal, regardless of the sample size

• For a large n, it says the sampling distribution of the sample mean is approximately normal, regardless of the population

• For a large n, it says the population is approximately normal

As the sample size gets larger, the standard error of the sampling distribution of the sample mean gets larger as well.

• True

• False

Suppose students' ages follow a skewed right distribution with a mean of 23 years old and a standard deviation of 4 years. If we randomly sample 200 students, which of the following statements about the sampling distribution of the sample mean age is INCORRECT?

• The mean of the sampling distribution is approximately 23 years old.

• The standard deviation of the sampling distribution is equal to 4 years.

• The shape of the sampling distribution is approximately normal.

A random sample of 250 students at a university finds that these students take a mean of 14.3 credit hours per quarter with a standard deviation of 1.7 credit hours. The 95% confidence interval for the mean is 14.3 ± 0.211. Interpret the interval.

• 95% of the students take between 14.089 to 14.511 credit hours per quarter.

• We are 95% confident that the average number of credit hours per quarter of students at the university falls in the interval 14.089 to 14.511 hours.

• We are 95% confident that the average number of credit hours per quarter of the sampled students falls in the interval 14.089 to 14.511 hours.

• The probability that a student takes 14.089 to 14.511 credit hours in a quarter is 0.95.

Fifteen SmartCars were randomly selected and the highway mileage of each was noted. The analysis yielded a mean of 47 miles per gallon and a standard deviation of 5 miles per gallon. Which of the following would represent a 90% confidence interval for the average highway mileage of all SmartCars?

In the US, 1 in 15,000 people has Huntington's disease. You take a random sample of 6,000 people. What is the mean of this binomial distribution?