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What proportion of a normal distribution is located in the tail beyond z = 2.00?

Statistical power is the probability that a statistical test will  ________

A vertical line is drawn through a normal distribution at z = 1.20.  What proportion of the distribution is on the left-hand side of the line?

A normal distribution has a mean of µ = 40 with σ = 10.   What proportion of the scores in this distribution are greater than X = 55?

A sample of n = 4 scores is obtained from a population with µ = 70 and σ = 8.  If the sample mean corresponds to a z-score of 2.00, then what is the value of the sample mean?

Even if a treatment has no effect, it is still possible to obtain an extreme sample mean that is very different from the population mean.  What outcome is likely if this happens?

What z-score values form the boundaries for the middle 60% of a normal distribution?

What does it mean for a z-score for a sample mean, or a test statistic, to be statistically significant?

On Halloween, Oprah puts candy out in a bowl – there are 20 Reese’s, 25 Junior Mint boxes, and 15 Laffy Taffys. When the first trick-or-treater comes by, what is the probability they choose a Laffy Taffy?

A sample of n = 4 scores is obtained from a population with µ = 70 and σ = 8.  If the sample mean corresponds to a z-score of 2.00, then what is the value of the sample mean?