An Urn Contains Five Red R Balls Numbered 1, 2

question 32

Multiple Choice

An urn contains five red R balls numbered 1, 2, 3, 4 and 5, four white W balls numbered 6, 7, 8 and 9, and three black B balls numbered 10, 11 and 12. A ball is drawn from the urn. What is the probability that it is not black? ​

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Definitions:

Conditional Probability

The probability of one event occurring with some relationship to one or more other events.

P(A|B)

The probability of event A occurring given that event B has already occurred, representing a conditional probability.

Complement

In probability theory, the complement of an event is the set of all outcomes in the sample space that are not included in the event itself.

Independent

In statistical analysis, this term describes variables that are not affected by changes in other variables.