MAS202 - Review Distributions

What is the relationship among the mean, median, and mode in a symmetrical distribution?

• The mode is always the largest value

• The median is the largest value

• They are all equal

• The mean is always the smallest value

• None of the other choice is correct

The time between arrivals of customers at a bank between noon and 1 pm has a uniform distribution over an interval from 0 to 120 seconds.

What is the standard deviation of waiting time?

• 34.64102

• 34.92850

• 1200

• 60

• None of the other choices is correct

• 0.2420

• 0.3401

• 0.7580

• 0.2580

• None of the other choices is correct

Let X be a continuous uniform distribution over the interval [2, 4]

Find the standard deviation of X.

• 3.5

• 0.5774

• 0.3333

• 3

• None of the other choices is correct

A multiple choice test contains 10 questions, each with four answers. Assume a student just guesses on each question.

What is the probability that the student answers 4 questions correctly?

• 0.0583992

• 0.145998

• 0.2502823

• 0.9218731

• None of the other choices is correct

• 0.93319

• 0.02275

• 0.04406

• 0.9545

• None of the other choices is correct

• 0.2177

• 0.1003

• 0.7823

• 0.2823

• None of the other choices is correct

The time that one needs for the next bus to arrive is uniformly distributed from 5 minutes to 17 minutes. What is the standard deviation of waiting time?

• 3.46

• 3.60

• 3.65

• 3.75

Sample of size 100 are randomly selected from the population of the scores of FPT's students. If population mean is 7.5 and the population variance is 0.3, what is the sampling distribution of the sample mean?

• Mean 7.5 and variance 0.300

• Mean 7.5 and variance 0.030

• Mean 7.5 and variance 0.003

• Mean 7.5 and variance 3.000

• None of the other choices is correct

• 0.1596

• 0.8404

• 0.4728

• 0.5272