The T-Test for Two Means Is Appropriate Whenever the Two $\sigma_{1}, \sigma_{2}$

question 20

Multiple Choice

The t-test for two means is appropriate whenever the two population variances ( $\sigma_{1}, \sigma_{2}$ ) are ______.

• A) unknown
• B) known
• C) normally distributed
• D) beyond the critical value for statistical significance

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Definitions:

Z Scores

Standardized scores that indicate how many standard deviations an element is from the mean of the dataset. They are used in statistics to compare different data points.

Normal Curve

A graphical representation of a distribution where the majority of data points are concentrated around the mean, decreasing in frequency the farther they are from the mean.

Percentages

A portion or share of a whole, expressed as a fraction of 100.

Normal Curve

A symmetrical, bell-shaped curve that represents the distribution of a set of data, indicating that data near the mean are more frequent in occurrence than data far from the mean.