TABLE 12-9
Four Surgical Procedures Currently Are Used

question 63

True/False

TABLE 12-9
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 center wants to compare the proportion of clear operations for the 4 procedures, and collects the following numbers of patients from their own records:
$$\begin{array}{l}\text {\quad\quad\quad\quad\quad\quad\quad Procedure }\\\begin{array} { l | r r r r | r } & \text { A } & \text { B } & \text { C } & \text { D } & \text { Total } \\\hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \\\text { Return } & 11 & 15 & 9 & 11 & 46 \\\hline \text { Total } & 38 & 56 & 30 & 18 & 142\end{array}\end{array}$$ They will use this information to test for a difference among the proportion of clear operations using a chi-square test with a level of significance of 0.05.
-Referring to Table 12-9, there is sufficient evidence to conclude that the proportions between procedure B and procedure D are different at a 0.05 level of significance.

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Definitions:

LIFO method

An inventory cost-flow assumption where the last items purchased or produced are the first to be expensed as sold, opposite of FIFO.

Cost of merchandise sold

The total expense incurred to produce or purchase the goods sold by a company during a specific period.

Year amount

Typically refers to the total sums of money or quantities measured over the course of a year in financial or quantitative analyses.

Average costing

Average costing is an inventory costing method where all costs of inventory are averaged over the goods available for sale, providing a medium cost per unit.