Instruction 15-8
Four Surgical Procedures Currently Are Used to Install

question 79

Short Answer

Instruction 15-8
Four surgical procedures currently are used to install pacemakers.If the patient does not need to return for follow-up surgery,the operation is called a "clear" operation.A heart centre wants to compare the proportion of clear operations for the four procedures,and collects the following numbers of patients from their own records:
| Procedure |
$$\begin{array} { | l | c | c | c | c | c | } \hline & \mathrm { A } & \mathrm { B } & \mathrm { C } & \mathrm { D } & \text { Total } \\\hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \\\hline \text { Return } & 11 & 15 & 9 & 11 & 46 \\\hline \text { Total } & 38 & 56 & 30 & 18 & 142 \\\hline\end{array}$$ They will use this information to test for a difference among the proportion of clear operations using a chi-square test with a 0.05 level of significance.
-Referring to Instruction 15-8,the test will involve ________ degree(s)of freedom.

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Definitions:

Sudden Increase In Demand

A rapid and unexpected rise in the desire or need for a specific product or service, which can impact market dynamics.

Long-Term Relationships

Enduring associations between companies and their stakeholders, such as customers or suppliers, typically characterized by trust, loyalty, and mutual benefit over time.

Fixed-Position Layout

An operational strategy where the product remains stationary, and workers, materials, and equipment are moved as needed.

Product Layout

An arrangement of equipment or workstations in the sequence that production operations are performed to manufacture a product.