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)