Use Bayes' Rule to Find the Indicated Probability

question 44

Multiple Choice

Use Bayes' rule to find the indicated probability.
-An water well is to be drilled in the desert where the soil is either rock,clay or sand.The probability of rock P(R) = 0.53.The clay probability is P(C) = 0.21.The sand probability is P(S) = 0.26.It if it rock,a geological test gives a positive result with 35% accuracy.If it is clay,this test gives a positive result with 48% accuracy.The test gives a 75% accuracy for sand.Given the test is positive,what is the probability that soil is rock,P(sand | positive) ?

• A)P(sand | positive)= 0.405
• B)P(sand | positive)= 0.385
• C)P(sand | positive)= 0.26
• D)P(sand | positive)= 0.209

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Definitions:

Standard Cost

An estimated or pre-determined cost of performing an operation or producing a good, used in budgeting and pricing.

Actual Cost

The tangible and realized expense incurred for materials, labor, and overhead in the production of goods or services.

Standard Cost Systems

An accounting method that uses standard costs for direct materials, labor, and overhead to help managers control business costs.

Performance Evaluation

The formal assessment process of an employee's job performance, typically conducted through reviews and meetings.