The Random Variable X Represents the Number of Boys in a Family

question 46

Multiple Choice

The random variable x represents the number of boys in a family with three children. Assuming that births of boys and girls are equally likely, find the mean and standard deviation for the random variable x.

• A) mean: 1.50; standard deviation: .87
• B) mean: 2.25; standard deviation: .87
• C) mean: 1.50; standard deviation: .76
• D) mean: 2.25; standard deviation: .76

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Definitions:

Secondary Line Voltage

The voltage seen across the secondary winding of a transformer or at the output of a power supply, typically lower than the primary voltage.

Turns Ratio

The ratio of the number of turns in the primary winding to the number of turns in the secondary winding of a transformer, affecting its voltage transformation.

Delta-Wye Transformer

A type of electrical transformer that can convert between delta and wye (star) configurations, facilitating the transformation of voltage levels and phase shift adjustments in power systems.

Wye-Delta Transformer

A transformer configuration used to shift between high and low voltages in a three-phase electrical system, involving a star (Wye) connection and a delta connection.