An Elementary School Principal Wants to Know the Mean Number

question 630

Multiple Choice

An elementary school principal wants to know the mean number of children in families whose
Children attend this school. He checks all the families using the school's registration records, and we
Create a 95% confidence interval based on a t-distribution. This procedure was not appropriate.
Why?

• A) The population standard deviation is known, so he should have used a z-model.
• B) The recent record-setting family with twelve children is probably an outlier.
• C) The entire population of families was gathered so there is no reason to do inference.
• D) At a given school families are not randomly selected.
• E) Since these families are from only one school, the family sizes may be skewed.

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Definitions:

ECG

A test that records the electrical activity of the heart to detect heart conditions.

ECGs

Electrocardiograms, a medical test that measures the electrical activity of the heart to identify abnormalities.

Atrioventricular Valves

Heart valves located between the atria and ventricles, enabling blood flow from the atria to the ventricles while preventing backflow.

Semilunar Valves

Valves located at the exit of both the left and right ventricles of the heart, which prevent backflow of blood into the ventricles.