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Which summary statistic is most affected by extreme values?

A sample proportion is stored in cell B2, the sample size is stored in cell B3, and the confidence level is 95%. Write an Excel formula to compute the margin of error for a population proportion confidence interval. Include all necessary Excel functions. Use cell references for inputs, as described above. Write as if you are using a single cell to compute the margin of error, including the formula/function for the critical value. Use B2 for p-hat, use 1-B2 for q-hat, and use B3 for the sample size.

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A learning-center coordinator studies whether weekly tutoring hours x predict module assessment score y. The data were entered in the order students completed the course, not in sorted x-value order. Use the following data to compute the simple linear regression equation and then predict y when x = 5.3. x              y4.8          38.41.2          17.67.2          49.63.6          29.86.0          42.02.4          21.2 Enter the slope [slope]____, intercept [intercept]____, and predicted ŷ for x = 5.3 [y-hat]____.(round each answer to 2 decimals)

Suppose a researcher claims: μ₁ ≥ μ₂ The hypotheses are set up as: H₀: μ₁ ≥ μ₂; H₁: μ₁ < μ₂ If the test decision is reject H₀, then the original claim is supported.

A two-proportion test has H₁: p₁ > p₂ and α = 0.07. Enter the left [left]_____ and right [right]_____critical values. If there is no critical value enter “na”. (round to 3 decimals)

A two-sample test has H₁: p₁ ≠ p₂ and alpha = 0.04 Which Excel formula gives the correct right critical value?

A variance test has: H1:σ2>144 α=0.04 degrees of freedom df=22 Using Excel’s right-tail chi-square function, which formula gives the correct critical value?

A random sample of 420 customers finds that 36% prefer self-checkout. A 95% confidence interval will be constructed for the true population proportion. What is the margin of error E?

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?