An Urn Contains 50 Black Balls and 20 Blue Balls

question 44

Multiple Choice

An urn contains 50 black balls and 20 blue balls.If you select 30 balls at random,what is the expected number of black balls?

• A)25.42
• B)23.76
• C)21.43
• D)19.94
• E)17.30

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Definitions:

Cohort

A cohort is a group of people banded together or treated as a group, often in a study, characterized by a shared attribute, such as age or experience, over a specific period of time.

Gender Differences

Variations in characteristics, behaviors, or attitudes between males and females, often shaped by biological, social, and cultural factors.

Play Behavior

Activities performed for self-amusement that have behavioral, social, and psychomotor benefits, often observed in children and young animals.

Strange Situation

A research method used in developmental psychology to assess attachment styles in children by observing their reactions when separated and reunited with their caregivers.