Question

Which of the following is not a characteristic of a normal variable?

Select one:

a. It assumes a countable number of values.

b. The probability of each individual value is virtually 0.

c. The mean and the median are always the same.

d. It is a continuous random variable.

Donald has in his pocket three coins: two fair coins and a two-headed coin. He selects one of the coins at random; when he tosses it, it shows head. What is the probability that the selected coin is a two-headed coin?

Select one:

a. 0.25

b. 0.75

c. 0.333

d. 0.5

Suppose that the daily demand for regular gasoline at a gas station is normally distributed with a mean of 1,000 gallons and a standard deviation of 100 gallons. The next delivery of gasoline is scheduled later today at the close of business. What is the minimum amount of regular gasoline that the station must have in storage so that there is a 90% chance it will have enough to satisfy today’s demand?

Select one:

a. 836

b. 1,128

c. 1,165

d. 872

Suppose the differences in GPAs of all the students in one university in the two most recent semesters (the GPA in the current semester minus the GPA in the last semester) are normally distributed with a mean of 0.2 and a standard deviation of 0.18. What is the probability that a randomly picked student from this university is having a lower GPA in the current semester than what he/she received in the last semester?

Select one:

a. 0.5

b. 0.1335

c. 0.8665

d. 0

Answer 1

Ans (1) The statement is not a characteristic of normal variable that