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The time required to complete a software update is normally distributed with mean μ = 38 minutes and standard deviation σ = 5 minutes. What is the probability that a randomly selected update takes more than 45 minutes?

An agronomist studies yield using 4 seed varieties, Factor A, and 3 irrigation levels, Factor B. There are 3 replicated plots in each variety/irrigation combination. Excel gives: Interaction p-value = 0.0524Factor A p-value = 0.0007Factor B p-value = 0.0041 Using the instructions above, and assuming as alpha = 0.05, enter yes or no to the following questions: Is the interaction significant? [intsig]_____ Are all Factor A’s different from each other? [F1sig]_____ Is as least one Factor B different from at least one other Factor B? [F2sig]____

An insurance auditor claims that the variance in monthly claim amounts is not equal to 400. Complete the written hypothesis shown below. Use only these possible signs: =, =,  [H0H1]____ (enter H0 or H1): mu [sign]______ (enter the correct sign) [value]_____ (enter the value)

A sample of 28 shipping delays has a sample variance of 14.7. The hypothesized population variance is 21. Use: n=28 s2=14.7 σ2=21 What is the chi-square test statistic?

A medical-device company compares mean battery-life ratings from three independent labs. Excel gives the following one-way ANOVA output: Source: Between GroupsSS = 18.240df = 2MS = 9.120F = 5.413P-value = 0.014F crit = 3.555 Using α = 0.05, which conclusion is correct?

A fitness center predicts monthly membership renewals Y using the number of promotional emails sent X₁ and the number of personal training consultations X₂. Excel multiple regression output gives: Intercept = 31.480X₁ coefficient = 0.275X₂ coefficient = 1.640R Square = 0.818Significance F = 0.004 For a month with X₁ = 84 promotional emails and X₂ = 19 consultations, what is the predicted number of membership renewals, rounded to 1 decimal?

A customer-service department uses hold time x, in minutes, to predict satisfaction score y. The regression equation is: ŷ = 88.314 − 6.205x For x = 7.2 minutes, what is the predicted satisfaction score?

A researcher uses hours of sleep to predict reaction-time score. Excel regression output gives: Multiple R = 0.522R Square = 0.272Significance F = 0.121Intercept = 38.600Sleep Hours coefficient = 2.180 Using α = 0.10, which conclusion is correct?

A two-sample mean test has H₁: μ₁ < μ₂ and α = 0.08. Which Excel formula gives the correct left critical value?

Find the z-value such that the area to the right of z is 0.035. (round to 3 decimals)