Exam 4: Discrete Random Variables

For a binomial experiment, the probability of success is 40% and the number of trials is 5. Let X represent the number of successes. -Find the variance of X.

The J.O. Supplies Company buys calculators from a foreign supplier. The probability of a defective calculator is 10%. -If 100 calculators are selected at random,what is the standard deviation of the number of defectives?

For a binomial experiment, the probability of success is 40% and the number of trials is 5. Let X represent the number of successes. -Find P(X ≤ 1).

An important part of the customer service responsibilities of a cable company relates to the speed with which trouble in service can be repaired. Historically, the data show that the likelihood is 0.75 that troubles in a residential service can be repaired on the same day. For the first five troubles reported on a given day, what is the probability that: -All five will be repaired on the same day?

If n = 20 and p = .4,then the mean of the binomial distribution is

Twenty coins are tossed.What is the probability of getting exactly 10 heads?

A vaccine is 95 percent effective. What is the probability that it is not effective for: -More than one out of 20 individuals?

According to data from a federal blood program, 40% of all individuals have type A blood. If six individuals give blood, find the probability -At least 3 of the individuals have type A blood

The J.O. Supplies Company buys calculators from a foreign supplier. The probability of a defective calculator is 10%. -If 100 calculators are selected at random,what is the standard deviation of the number of defectives?

An important part of the customer service responsibilities of a cable company relates to the speed with which trouble in service can be repaired. Historically, the data show that the likelihood is 0.75 that troubles in a residential service can be repaired on the same day. For the first five troubles reported on a given day, what is the probability that: -Fewer than two troubles will be repaired on the same day?

An important part of the customer service responsibilities of a cable company relates to the speed with which trouble in service can be repaired. Historically, the data show that the likelihood is 0.75 that troubles in a residential service can be repaired on the same day. For the first five troubles reported on a given day, what is the probability that: -Find the mean number of troubles repaired on the same day

Suppose that of the six randomly selected individuals,3 have group A blood.Based on the probability in question 100,would you believe the data from the state blood program? Why or why not?

For a random variable X,the mean value of the squared deviations of its values from their expected value is called its _____.

Determine the standard deviation of the number of defective units for 32 sheets of metal.

If x is a Poisson random variable with a mean of 10,what is the probability that x is equal to 8?

Historical data shows that the average number of patient arrivals at the intensive care unit of General Hospital is 3 patients every 2 hours. Assume that the patient arrivals are distributed according to Poisson distribution. -Determine the probability of at least 4 but no more than 8 patients arriving in a three-hour period.

If X is a binomial random variable,then the standard deviation of X is given by ______.

An insurance company will insure a $75,000 car for its full value against theft at a premium of $1500 per year. Suppose that the probability that the car will be stolen is 0.0075. -Calculate the insurance company's expected net profit.

What is the standard deviation for this distribution?

A store owner records the number of customers who make a purchase for the first five customers during a particular day.In this situation,X may be 0,1,2,3,4,or 5.