Chapter 5 Practice Questions

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 ________ distribution

poisson

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

random variable

Experiment or random variable? If random, say if discrete or continuous? # of cars arriving at a tollbooth

random variable; discrete

Experiment or random variable? If random, say if discrete or continuous? # of returns containing errors

random variable; discrete

a continuous random variable may assume _______ in an interval

any value

the weight of an object is an example of ________ random variable

continuous

Characteristics of: exponential (ch. 6)

continuous; time or distance

an experiment consists of making 80 telephone calls in order to sell a particular insurance policy. the random variable in this experiment is a ________ random variable

discrete

the binomial probability distribution is used with a _________ random variable

discrete

Characteristics of: binomial

discrete; 2 outcomes; independent outcomes; draw w/ replacement

Characteristics of: hypergeometric

discrete; 2 outcomes; independent outcomes; draw w/o replacement

the poisson probability distribution is used with a __________ random variable that involves ________ or _________

discrete; time or distance

another name for the mean of a distribution is ________

expected value

Experiment or random variable? If random, say if discrete or continuous? take a 20 question exam

experiment

Experiment or random variable? If random, say if discrete or continuous? observe an employee's work

experiment; # of hours is continuous

Experiment or random variable? If random, say if discrete or continuous? weigh a shipment of goods

experiment; weight is continuous

When sampling without replacement, the probability of obtaining a certain sample is best given by a ________ distribution

hypogeometric

Characteristics of: normal (ch. 6)

standard deviation is +, m can be -1, 0, 1; standard normal of Z has a deviation of 1

Characteristics of: poisson

discrete; time or distance

list 2 conditions required for a discrete probability function

1) 0 < f(x) < 1 2) Ef(x)= 1 (between 0 and 1, must add up to 1)

If you are conducting an experiment where the probability of a success is .02 and you are interested in the probability of 4 successes in 15 trials, the correct probability function to use is the _________ distribution

binomial

a production process produces 2% defective parts. A sample of five parts from the production process is selected. What is the probability that the sample contains exactly two defective parts?

binomial

a probability distribution showing the probability of x successes in n trials, where the probability of success does not change from trial to trial, is termed a

binominal

Characteristics of: uniform (ch. 5 and 6)

both in ch.5 and 6; discrete (rolling a dice) or continuous (travel time); constant f(x)