OBA 311 Midterm HW #2

Given that z is a standard normal random variable, what is the value of z if the area to the right of z is 0.5?

0

Which of the following is not a characteristic of the normal probability distribution?

99.72% of the time the random variable assumes a value within plus or minus 1 standard deviation of its mean

Which of the following is a characteristic of an experiment where the binomial probability distribution is applicable?

Exactly two outcomes are possible on each trial

Which of the following is not a property of a binomial experiment?

The probabilities of the two outcomes can change from one trial to the next

A continuous random variable may assume

any numerical value in an interval or collection of intervals

The uniform, normal, and exponential distributions

are all continuous probability distributions

The z score for the standard normal distribution

can be either negative or positive

An exponential probability distribution

is a continuous distribution

The variance Var(x) for the binomial distribution is given by equation

np(1 - p)

A numerical description of the outcome of an experiment is called a

random variable

For a continuous random variable x, the probability density function f(x) represents

the height of the function at x

The key difference between the binomial and hypergeometric distribution is that, with the hypergeometric distribution

the probability of success changes from trial to trial

A uniform probability distribution is a continuous probability distribution where the probability that the random variable assumes a value in any interval of equal length is

the same for each interval

For a normal distribution, a positive value of z indicates that

the sample mean is larger than the population mean

The binomial probability distribution is used with

a discrete random variable

The assembly time for a product is uniformly distributed between 6 to 10 minutes. What is the value of probability density function in the interval between 6 and 10?

0.25

A continuous random variable is uniformly distributed between a and b. The probability density function between a and b is

1/(b - a)

In the textile industry, a manufacturer is interested in the number of blemishes or flaws occurring in each 100 feet of material. The probability distribution that has the greatest chance of applying to this situation is the

Poisson Distribution

If one wanted to find the probability of ten customer arrivals in an hour at a service station, one would generally use the

Poisson probability distribution

The weight of an object is an example of

a continuous random variable

The Poisson probability distribution is used with

a discrete random variable

Which of the following is a required condition for a discrete probability function?

∑f(x) = 1 for all values of x