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Ch. 4 - Probability
Triola - Elementary Statistics 14th Edition
Triola14th EditionElementary StatisticsISBN: 9780137366446Not the one you use?Change textbook
Chapter 4, Problem 4.2.1

Notation When randomly selecting a new smartphone, D denotes the event that it has a manufacturing defect. What do P(D) and P(D) represent?

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Step 1: Understand the notation. In probability, 'P(D)' represents the probability of event 'D' occurring. Here, 'D' is the event that a randomly selected smartphone has a manufacturing defect.
Step 2: Clarify the meaning of 'P(D)'. It quantifies the likelihood of the event 'D' happening, expressed as a value between 0 and 1, where 0 means the event is impossible and 1 means the event is certain.
Step 3: Recognize that 'P(D)' is a mathematical representation of the probability. For example, if 5% of smartphones have defects, then P(D) = 0.05.
Step 4: If the problem also refers to 'P(D)', it is likely asking for the same probability value, as 'P(D)' is the standard notation for the probability of event 'D'.
Step 5: To calculate P(D) in practice, you would divide the number of defective smartphones by the total number of smartphones in the sample or population, using the formula: P(D)=Number of defective smartphonesTotal number of smartphones.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Probability

Probability is a measure of the likelihood that a particular event will occur, expressed as a number between 0 and 1. In this context, P(D) represents the probability that a randomly selected smartphone has a manufacturing defect. Understanding probability is essential for interpreting the likelihood of events in statistics.
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Event

An event in probability is a specific outcome or a set of outcomes from a random experiment. In this case, D is the event that a smartphone has a manufacturing defect. Recognizing events helps in calculating probabilities and understanding the context of statistical analysis.
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Notation in Probability

Notation in probability provides a standardized way to represent events and their probabilities. P(D) specifically denotes the probability of event D occurring. Familiarity with this notation is crucial for effectively communicating and solving problems in statistics.
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