Exam 6: Continuous Random Variables

The cashier service time at the local branch of the Rivertown bank has an exponential distribution with a mean of 2.5 minutes.What is the probability that the service time: Is no more than 3 minutes?

A probability distribution that describes the time or space between successive occurrences of an event is a(n)_____ probability distribution.

Consider a normal population with a mean of 10 and a variance of 4.Find P(X > 18).

If the scores on an aptitude test are normally distributed with mean 500 and standard deviation 100,what proportion of the test scores are less than 585?

The mean and median are the same for an exponential distribution.

If the random variable of x is normally distributed,68.26% of all possible observed values of x will be within two standard deviations of the mean.

What is the probability that a standard normal random variable will be between -2 and 2?

The flying time of a drone airplane has a normal distribution with mean 4.76 hours and standard deviation of .04 hours.What is the probability that the drone will fly: More than 4.80 hours?

The life of a light bulb is exponentially distributed with a mean of 1,000 hours.What is the probability that the bulb will last: Less than 800 hours?

Suppose the daily change in price of a stock is normally distributed with mean = .20 and standard deviation = .30.What price change is associated with the 25^th percentile?

The flying time of a drone airplane has a normal distribution with mean 4.76 hours and standard deviation of .04 hours.What is the probability that the drone will fly: Less than 4.66 hours?

The population of lengths of aluminum-coated steel sheets is normally distributed with a mean of 30.05 inches and a standard deviation of 0.2 inches. What is the probability that a sheet selected at random from the population is between 30.25 and 30.65 inches long?

The relationship between the standard normal random variable Z and normal random variable X is that:

Suppose that the waiting time for a license plate renewal at a local office of a state motor vehicle department has been found to be normally distributed with a mean of 30 minutes and a standard deviation of 8 minutes.What is the probability that a randomly selected individual will have a waiting time at least 10 minutes?

The number of standard deviations that a value x is from the mean is a(n)_____.

Consider a normal population with a mean of 10 and a standard deviation 2. Find P(X = 10).

The average time a subscriber spends reading the local newspaper is 49 minutes.Assume the standard deviation is 16 minutes and that the times are normally distributed. What is the probability a subscriber will spend at least 1 hour reading the paper?

A uniform distribution f(x)is a continuous probability distribution which says the probability that x is in any 2 intervals of equal length is the same.

A study shows that employees that begin their work day at 9:00 a.m.vary their times of arrival uniformly from 8:40 a.m.to 9:30 a.m.The probability that a randomly chosen employee reports to work between 9:00 and 9:10 is:

The height of a probability curve f(x)at a particular point indicates the value of a probability for a given value of a random variable x.