When building a confidence interval for a population mean, we use the Z-interval when:

Suppose the sample space S = {1, 2, 3, 4, 5, 6, 7, 8, 9}, event A = {1, 2, 3}, and event B = {1, 3, 5}. (For parts a, b, and c, separate the elements with commas and put your answers in numerical order.)   a. Find BC = {} b. Find A

Assume that whether it rains today or tomorrow is independent of each other. The probability that it rains today is 0.32 and the probability that it rains tomorrow is 0.87. (Round to 3 decimal places)   a. What is the probability that it rains today and tomorrow? b. What is the probability that it rains at least one of the days?

Consider the following discrete probability distribution. x P(X = x) 10 0.35 20 0.10 30 0.15 40 0.40 a. Find the probability that X is greater than 20. b. Find the probability that X is less than 40. c. Find the expected value, µ, of X.

What is the symbol used to represent the population mean?

Consider the following boxplot of midterm scores from a biology class. a. State the shape of the distribution b. Considering the shape of the distribution, what is the best measure of central tendency? c. Considering the shape of the distribution, what is the best measure of dispersion? d. Estimate the value of Q3

A histogram of a set of data indicates that the distribution of the data is right skewed. Which measure of central tendency will be larger, the mean or the ​median?

A store manager is interested in the percentage of employees who are willing to work extra hours. The manager takes a random sample of 50 employees. Of the sampled employees, 26% said they were willing to work more.   a. The population is . b. The sample is . c. The value of 26% is a .  

Given the graph, a. What is the shape? b. If 200 people were sampled, how many preferred soccer?

Given the following graph, a. What is the shape of the distribution? b. What percentage of donuts had calories between 250 and 350 calories?