Blog

A clinic estimates that 12.5% of people tested are positive. Which Excel formula computes the probability that the next 2 people tested both test positive?

A probability model gives P(at least one success)=0.672. Which statement is correct?

Instructions: Use the data table below. Assume the table is entered in Excel exactly as shown in cells A1:E13, with headers in row 1 and data in rows 2–13. Column A is Respondent ID; Column B is Plan; Column C is number of Purchases; Column D is Wait time in Minutes; Column E is a Satisfaction rating on 1-5 scale.   If Excel formula =COUNT(C2:C13) is used, what value is returned?

A testing center finds that 14% of people tested are positive for a certain virus. What is the probability that the next 2 people tested both test positive? (round to 3 decimals)

A researcher compares mean tensile strength among three fabric treatments: A, B, and C. Which is the correct null hypothesis for a one-way ANOVA?

Find the probability that a standard normal variable is less than 1.37. (round to 3 decimal places) That is, find: P(z < 1.37)

A campus dining manager claims that the average daily number of lunch transactions is different from 425. A random sample of days will be used to test the claim. Which setup is correct?

A school reports that 30% of students take the bus. If 5 students are randomly selected independently, what is the probability that none of the 5 students takes the bus? (round to 3 decimals)

At a clinic, 18% of patients arriving for a screening test positive for a condition. Assuming independent outcomes, what is the probability that the next 2 patients both test positive? (round to 3 decimals)

A small retailer studies whether weekly local advertising exposure x predicts customer inquiry count y. The x-values are not listed in increasing order, and one lower x-value has an unusually low y-value, so use regression computation rather than a visual estimate. Use the following data to compute the simple linear regression equation and then predict y when x = 27. x              y30           42.3510           18.9525           40.5015           21.8035           53.2020           33.65 Enter the slope [slope]____, intercept [intercept]____, and predicted ŷ for x = 27 [y-hat]____.(round each answer to 2 decimals)