Exam 5: Discrete Random Variables and Their Probability Distribution

A continuous random variable is a random variable:

Use the following to answer questions : The following table lists the probability distribution of the number of HD-TVs owned by all families in a city. -The standard deviation of the number of HD-TVs owned by these families,rounded to three decimal places,is:

The binomial probability distribution is symmetric if:

For the probability distribution of a discrete random variable x,the sum of the probabilities of all values of x must be:

Eight percent of all college graduates hired by companies stay with the same company for more than five years.The probability,rounded to four decimal places,that in a random sample of 11 such college graduates hired recently by companies,exactly 3 will stay with the same company for more than five years is:

Use the following to answer questions : The following table lists the probability distribution of a discrete random variable x: -The standard deviation of the random variable x,rounded to three decimal places,is:

Use the following to answer questions : The following table lists the probability distribution of a discrete random variable x: -The standard deviation of the random variable x,round to three decimal places,is:

All 10 of the orangutans at a certain zoo contract a very serious disease which claims 84% of its victims (if an orangutan contracts the disease,the probability that it will die is 0.84).What is the probability,rounded to four decimal places,that exactly 1 of the orangutans at this zoo will survive?

Use the following to answer questions : The following table lists the probability distribution of the number of refrigerators owned by all families in a city. -The probability that a randomly selected family owns at most one refrigerator is:

Which of the following is not an example of a discrete random variable?

It costs $7.25 to play a very simple game,in which a dealer gives you one card from a deck of 52 cards.If the card is a heart,spade,or diamond,you lose.If the card is a club other than the queen of clubs,you win $11.50.If the card is the queen of clubs,you win $49.50.The random variable x represents your net gain from playing this game once,or your winnings minus the cost to play.What is the mean of x,rounded to the nearest penny?

The parameters of the binomial probability distribution are:

Use the following to answer questions : The following table lists the probability distribution of the number of refrigerators owned by all families in a city. -The probability that a randomly selected family owns less than two refrigerators is:

Use the following to answer questions : A manufacturer packages bolts in boxes containing 100 each.Each box of 100 bolts contains,on average,6 defective bolts.The quality control staff randomly selects a box at the end of the day from an entire production run. -What is the probability,rounded to four decimal places,that the box will contain at most 6 defective bolts?

Which of the following is an example of a binomial experiment?

In binomial experiments,the outcome called a "success" is an outcome:

Use the following to answer questions 34-35: The following table lists the probability distribution of a discrete random variable x: -The mean of the random variable x is:

A discrete random variable is a random variable:

Forty-four percent of customers who visit a department store make a purchase.The probability,rounded to four decimal places,that in a random sample of 12 customers who will visit this department store,exactly 7 will make a purchase is:

Thirty percent of law students who sit for a bar exam pass it the first time.The probability,rounded to four decimal places,that in a random sample of 15 law students who will sit for the bar examination,at most 4 will pass it the first time is: